Metal hydrides are used as anode material in nickel metal hydride batteries and are of particular interest because of the potential to be a part of energy systems completely involving renewable sources (e.g. solar power, wind power etc.). Preparation and electrochemical characterization of metal hydride electrodes have not previously been performed at the Department of Chemistry – Ångström Laboratory. Two basic techniques that are desired to be used in the characterization are cyclic voltammetry and chronopotentiometry. This thesis work is aimed at preparation and electrochemical characterization of a metal hydride electrode and, as a complement, study the electrode with X-ray diffraction. LaNi3.55Co0.75Mn0.4Al0.3, a standard material for metal hydride electrodes previously studied by Khaldi et al. was chosen, to ensure that electrochemical absorption of hydrogen was possible, and to be able to compare electrochemical results [1-3]. LaNi3.55Co0.75Mn0.4Al0.3 was synthesized with arc melting, with additional annealing at 900˚C for five days, ground in a cemented carbide ball mill and sieved to less than 56 µm. Electrodes were prepared containing 90 wt.-% of LaNi3.55Co0.75Mn0.4Al0.3 powder, 5 wt.-% of polytetrafluoroethylene and 5 wt.-% of carbon black. The hydrogen absorption and desorption capabilities of the electrode were studied electrochemically with cyclic voltammetry and chronopotentiometry, and the structural changes associated with absorption of hydrogen was studied with X-ray diffraction. The capacity increased, probably from activation of the material, during initial cycling up to the maximum capacity of 294 mAh/g, obtained after 9 cycles, followed by a small decrease, probably caused by corrosion and passivation of the material, in capacity of the remaining 11 cycles. Activation of the material causes the charge and the discharge potential to shift to a more positive and a more negative value, respectively. The final values for the charge potential and the discharge potential were -841mV and -945 mV vs. Hg/HgO, respectively, after 16 cycles. Khalid et al. [1-3]reported a maximum capacity of 300 mAh/g, a charge potential of about -960 mV and a discharge potential of about -840 mV after 16 cycles the results obtained in this study are considered to be in good agreement with those reported. X-ray diffraction of the electrodes revealed, as expected, a cell volume change of the charged electrode compared to the discharged electrode. The change in cell volume corresponds to an estimated capacity of 303 mAh/g, which is very close to the, above mentioned, electrochemically obtained maximum capacity of 294 mAh/g.

In this thesis, a novel technique for measuring photoacid generation kinetics in chemically amplified photoresists was developed that utilizes capacitance measurements from interdigitated electrodes. In this technique, a chemically amplified photoresist is first coated onto the interdigitated electrode sensors. Then, capacitance measurements are recorded from the sensor as the photoresist is exposed to UV radiation. As acid is generated in the film during exposure, the net dielectric constant of the resist film changes, resulting in a change in the capacitance measured from the IDE sensor. By properly analyzing the observed capacitance response to exposure, it is possible to determine the kinetic rate constant for photoacid generation, or Dill C parameter. The discussion in this thesis describes four major areas of work performed. First, the basic development of the Dill C measurement technique and data analysis algorithm is described. Second, potential complications due to relative humidity changes, spin coating problems, and ambient base contamination are investigated. Next, the discussion turns to two key improvements to the measurement technique: the use of multi-frequency measurements to increase the capacitance signal, and the development of a normalized capacitance expression for improved data analysis. Finally, the effects of two critical components of chemically amplified resist solutions upon the technique are studied: protecting groups and background base quenchers.

A system for extracellular neural interfacing that had the capability for stimulation and recording at multiple electrodes was presented. As the core of this system was a custom integrated circuit (IC) that contained low-noise amplifiers, stimulation buffers, and artifact-elimination circuitry. The artifact-elimination circuitry was necessary to prevent the activity of the stimulation buffers from interfering with the normal functioning of the low-noise amplifiers. The integrated circuits were fabricated in in a 0.35 micron CMOS process. We measured input-referred noise levels for the amplifiers as low as 3.50 microvolts (rms) in the in the bandwidth 30 Hz-3 kHz, corresponding to the frequency range of neural action potentials. The power consumption was 120 microwatts, corresponding to a noise-efficiency factor of 14.5. It was possible to resume recording signals within 2 ms of a stimulation, using the same electrode for both stimulation and recording. A filtering algorithm to remove the post-discharge artifact was also presented. The filtering was implemented using a field-programmable gate array (FPGA). The filtering algorithm itself consisted of blanking for the duration of the stimulation and artifact-elimination, followed by a wavelet de-noising. The wavelet de-noising split the signal into frequency ranges, discarded those ranges that did not correspond to neural signals, applied a threshold to the retained signals, and recombined the different frequency ranges into a single signal. The combination of the filtering with the artifact-elimination IC resulted in the capability for artifact-free recordings.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 220-243). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.) in Chemistry--University of Maine, 2003. / Includes vita. Includes bibliographical references (leaves 181-196).

Thesis (Ph. D.)--State University of New York at Binghamton, Materials Science and Engineering Program, 2009. / Includes bibliographical references.

Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on Mar. 11, 2010). Includes bibliographical references (p. 42-45).

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xvi, 149 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Sheikh Akbar, Dept. of Materials Science and Engineering. Includes bibliographical references (p. 138-149).

Thesis (M. Phil.)--University of Hong Kong, 1980.

Thesis--Ph. D., University of Hong Kong. / Mimeographed.