This thesis describes a divide-and-conquer algorithm to improve the 3D boundary element method (BEM) for capacitance extraction. We divide large interconnect structures into small sections, set new boundary conditions using the borderfor each section, solve each section, and then combine the results to derive the capacitance. The target application is critical nets where 3D accuracy is required. The new algorithm is a significant improvement over the traditional BEMs and their enhancements, such as the "window" method where conductors far away are dropped, and the "shield" method where conductors hidden behind other conductors are dropped. Experimental results show that our algorithm is 25 times faster than the traditional BEM and 5 times faster than the window+shield method, for medium to large structures. The error of the capacitance computed by the new algorithm is within 2% for self capacitance and 7% for coupling capacitance, compared with the results obtained by solving the entire system using BEM. Furthermore, our algorithms gives accurate distributed RC, where none of the previous 3D BEM algorithms and their enhancements can.

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This thesis developed thin film extraction technique, which is a solid phase microextraction (SPME) technique with enhanced sensitivity, without sacrificing analysis time due to the large surface area-to-volume ratio of thin film. Thin film extraction was applied for both spot sampling and time weighted average (TWA) sampling in laboratory and on site. First, an electric drill coupled with a SPME polydimethylsiloxane (PDMS) fiber or a PDMS thin film was used for active spot sampling of polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Laboratory experiments demonstrated that the sampling rates of fiber and thin film can be predicted theoretically. The performance of a PDMS-coated stir bar at a constant stirring speed was also investigated. Compared with the fiber or the stir bar, the thin film sampler exhibited a higher sampling rate and much better sensitivity due to its higher surface-to-volume ratio and its larger extraction-phase volume. A new thin film active sampler was developed; field tests illustrated that it was excellent for rapid on-site water sampling due to its short sampling period, high sampling efficiency and durability. Second, modeling was applied to study the kinetics of fiber SPME and thin film extraction by COMSOL Multiphysics. The symmetry of absorption of analyte onto the fiber (or thin film) and desorption of calibrant from the fiber in static aqueous solution and a flow through system, was demonstrated by modeling. Furthermore, kinetic calibration method was illustrated to be feasible for fiber SPME in complex aqueous matrix and then was used to calculate the total concentration of analyte in the system. Third, thin film extraction was used in on-site sampling in Hamilton Harbour and for the determination of TWA concentrations of PAHs based on the kinetic calibration. When the thin film sampler, a fiber-retracted SPME field water sampler, and a SPME rod were used simultaneously, the thin film sampler exhibited the highest sampling rate compared to the other water samplers, due to its large surface-to-volume ratio. Fourth, partition equilibriums and extraction rates of PAHs were examined for live biomonitoring with black worms and for the PDMS thin-film in passive sampling mode. In the initial extraction stage, the extracted amounts per surface area by two samplers were similar indicating that thin-film samplers could mimic the behavior of black worms for passive monitoring. A good linear relationship between bioconcentration factors and film-water partition coefficients of PAHs demonstrated the feasibility of thin-film sampler for determining the bioavailability of PAHs in water. Finally, thin film extraction was used for the analysis of human skin and breath under different experimental conditions. Thin film technique could study several skin areas of one person, characterize the skins of different persons, and measure volatile fractions of cosmetic products that were released from the skin. The sampling time in the breath analysis could be further reduced to only 20 seconds when the thin film was rotated with a portable drill.

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A novel technique of direct copper precipitation from a loaded chelating extractant using hydrogen in an autoclave (pressure hydrogen stripping) was studied. In its simplest form, the reaction is given by / {CuL(,2)}(,org) + H(,2)(g) (--->) 2{HL}(,org) + Cu(s). / Kelex 100 (Sherex Chemical Co. - commercial solvent extraction reagent), an alkylated derivative of 8-hydroxyquinoline was used as the basis of the present investigation and represents HL in the above equation. / Two types of experiments were carried out: (a) those designed to study the chemical and thermal response of the extractant at high temperature and hydrogen pressures and (b) those which describe the chemistry and kinetics of hydrogen stripping. / The extractant was found to exhibit excellent chemical stability up to 573 K (300(DEGREES)C) and 2.76 MPa (400 psi) hydrogen in the absence of copper. Its chemical stability was somewhat reduced when loaded with copper. In the latter case, some limited hydrogenation of the quinoline nucleus of the extractant and some of the impurities present (furoquinolines) was observed. The chemical stability of the extractant was found to be enhanced when at least 0.52 M of a long-chain alcohol (decanol) was added to the organic solvent (0.4 M Kelex/kerosene). A slow thermal dissociation of the copper chelate was found to take place within the experimental temperature range studied (443 to 488 K). This resulted in copper precipitation and organic regeneration. / Copper in a powder form was found to precipitate rapidly from loaded Kelex 100/decanol/kerosene solvents by reaction with hydrogen at pressures between 0.52 and 4.00 MPa (75 and 580 psi) and temperatures from 443 to 488 K (170 to 215(DEGREES)C). The overall process has heterogeneous characteristics. Nuclei are provided through slow thermal dissociation of the copper chelate. The freshly produced metallic copper, acting autocatalytically accelerates the precipitation kinetics. Reduction of the Cu(II) chelate to Cu(I) complex appears to be the rate controlling step. / In addition to temperature and pressure, the effects of seeding, agitation, copper concentration, ligand concentration and copper chelate age were investigated. Some physical and chemical properties of the copper powder product were also determined.

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