Use of Nano Zero Valent Iron (nZVI) for treatment of different halogenated hydrocarbons, arsenic and various other contaminants has been proved successful. However, with so much diversified use of nZVI in the field and heighted attention to engineered nanoparticles, the environmental fate and impact of the nZVI remains unknown. The goal of this project was to evaluate the effects of different types of nZVI on Typha latifolia, a common wetland plant and hybrid poplar (Populous deltoids x Populous nigra), a woody plant used in phytoremediation. Plants grown hydroponically in a green house were dosed with different concentration of bare or bimetallic nZVI (with 10% nickel coating) for one to four weeks. The results showed that bare nZVI had toxic effects to Typha in higher concentrations but enhanced growth of plants at lower concentrations. Bare nZVI did not significantly affect the growth of poplars but bimetallic nZVI did impede the growth. Bimetallic nano particles were significantly more toxic and resulted in death of Typha within a week of dosing. Scanning electron microscope (SEM) clearly showed the adsorption of the nZVI on the plant root surface, confirmed by Energy dispersive x-ray (EDX) analysis. Transmission electron microscope (TEM) and Scanning Transmission electron microscope (STEM) confirmed the uptake of nZVI by poplar plant, but such internalization was not observed in case of Typha. However, uptake of the nanoparticles was only limited to the root and the translocation of particles to the shoot was not observed.

Fast and accurate diagnosis is always in demand by modern medical professionals and in the area of national defense. At present, limitations of testing speed, sample conditions, and levels of precision exist under current technologies, which are usually slow and involve testing the specimen under laboratory conditions. Typically, these methods also involve several biochemical processing steps and subsequent detection of low energy luminescence or electrical changes, all of which reduce the speed of the test as well as limit the precision. In order to solve these problems and improve the sensing performance, this project proposes an innovative CMOS magnetic biological sensor system for rapidly testing the presence of potential pathogens and bioterrorism agents (zoonotic microorganisms) both in specimens and especially in the environment. The sensor uses an electromagnetic detection mechanism to measure changes in the number of microorganisms--tagged by iron nanoparticles--that are placed on the surface of an integrated circuit (IC) chip. Measured magnetic effects are transformed into electronic signals that count the number and type of organisms present. This biosensor introduces a novel design of a conical-shaped inductor, which achieves ultra-accuracy of sensing biological pathogens. The whole system is integrated on a single chip based on the fabrication process of IBM 180 nm (CMOS_IBM_7RF), which makes the sensor small-sized, portable, high speed, and low cost. The results of designing, simulating, and fabricating the sensor are reported in this dissertation. / Ph. D.