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I have developed a technique that improves the speed, reproducibility, and sensitivity of the measurement of degree of equilibration in ordinary chondrites. The Fast Electron Microprobe technique (FEM) technique provides a continuous quantitative scale for the amount of thermal processing a particular sample has experienced. The Fast Electron Microprobe technique (FEM) allows us to quickly collect sufficient data to determine the homogeneity and composition of olivine and low-Ca pyroxene in ordinary chondrite thin sections. I have studied several meteorites that are homogenous in olivine composition, but heterogeneous in low-Ca pyroxene composition. One of these samples (ALH 85033) has previously been classified as an L4. The FEM technique allows reproducible measurements of the degree of thermal metamorphism in ordinary chondrites, improving our understanding of thermal processing of asteroids in the early solar system.

This dissertation presents a series of studies that describe the impacts of, among other things, temperature and kinematics on inter-level dielectric (ILD) and metal chemical mechanical planarization (CMP) processes. The performance of CMP is often evaluated in terms of removal rate, uniformity, planarization length, step height, defects and resulting topography such as erosion and dishing. The assessment of these parameters is significantly dependent on the selection of tool and consumable set (polishing pad or slurry type), as well as the kinematics involved in the process. Variations in pressure, sliding velocity, temperature and slurry flow rate are just a few of the dynamic inputs that can affect polishing performance. The studies presented in this dissertation focus on some of these external parameters and how they influence the mechanisms involved with the CMP process and their overall outcome on performance.Studies presented in this dissertation include topics such as the effects wafer-ring configurations and wafer geometries on the applied wafer pressure distribution across a wafer surface. In addition to this, another study related to understanding applied wafer pressure investigated the estimation of the effective (envelop) pressure for patterned shallow trench isolation (STI) wafers during CMP. When considering the regularity of issues such as changing wafer geometries and wafer feature patterns, these two studies provided significant insight on the potential issues that could arise during CMP when dealing with such events, as well as potential solutions for controlling such events.Another study in this dissertation investigated the effects of polishing pad type on dielectric CMP performance. Polishing pads varied in thickness and grooving, and tests were done to characterize the tribological and thermal behavior of the pads under a wide range of p × V and slurry flow rate conditions. Of key importance in this study was observing any combined effects between changes in platen set point temperature and pad type on ILD removal rate.The greatest contribution to this dissertation involved studies related to the role of temperature in CMP. These studies implemented variable platen set point temperatures to further understand the thermal effects on parameters such as removal rate and coefficient of friction (COF). As a result of these studies, a new removal rate model based on flash heating was developed to describe observed non-linear trends in removal rate. The application of this model has shown great utility in removal rate prediction when compared to prior models.

A thermal model is developed to find the distribution of stable near-surface ground ice on Mars that is in diffusive contact with the atmosphere for past and present epochs. Variations in the orbit of Mars are able to drive climate changes that affect both surface temperatures and atmospheric water content so the distribution of ground ice will vary significantly in past epochs. A technique is developed to correct the average water vapor density above the surface for depletion due to diurnal frost formation. Also presented is a simple model to estimate the atmospheric water content, based on the water vapor carrying capacity of the atmosphere over water ice on the martian surface.Maps of the distribution of ground ice are generated for the present epoch of Mars with varying amounts of water vapor in the atmosphere. The water vapor depletion scheme restricts the extent of stable ground ice as more water is put into the atmosphere so that ice never becomes stable at low latitudes. As the position of the perihelion varies, the extent of ground ice changes several degrees in the latitudinal extent, primarily in the northern hemisphere. The extent of ground ice is sensitive to the obliquity of Mars, however high obliquities are still not able to make ground ice stable at low latitudes. Finding ice is never stable at low latitudes is consistent with the lack of terrain softening at low latitudes and models that indicate Mars had high obliquities for much of its history.Also presented is the first L-band spectrum of an irregular satellite from the outer Solar System. Spectra of Himalia were obtained with the Visual and Infrared Mapping Spectrometer onboard the Cassini spacecraft. The Himalia spectrum is essentially featureless, showing a slight red slope and a suggestion of an absorption feature at 3 microns that would indicate the presence of water. Better measurements of the spectrum of Himalia, particularly in the region of the apparent 3-micron band, could help determine whether water is present, and if so, in what form.

This thesis presents a study of the cooling process of a solid block performed by a turbulent air flow channel. The study focuses on the turbulent flow and its influence in the heat transfer of the block. The first part of the thesis is an analysis of the different turbulent model and their adaptation on the necessities of this study. Once the turbulent model has been confirmed it makes a study of the behavior of the cooling process by CFD (Computational Fluid Dynamics), and an analysis of the numerical accuracy of this computational study. When the procedure of the study of the cooling process is defined it proposes some different variations in the initial solution to improve this process. The study concentrates in variations of the turbulence and the geometry of the studied block. Finally, the different improving are discussed analyzing parameters as the heat transfer, pressure drop, time consuming or energy consuming.

Under certain conditions, reactive chemicals may proceed into uncontrolled chemical reaction pathways with rapid and significant increases in temperature, pressure, and/or gas evolution. Reactive chemicals have been involved in many industrial incidents, and have harmed people, property, and the environment. Evaluation of reactive chemical hazards is critical to design and operate safer chemical plant processes. Much effort is needed for experimental techniques, mainly calorimetric analysis, to measure thermal reactivity of chemical systems. Studying all the various reaction pathways experimentally however is very expensive and time consuming. Therefore, it is essential to employ simplified screening tools and other methods to reduce the number of experiments and to identify the most energetic pathways. A systematic approach is presented for the evaluation of reactive chemical hazards. This approach is based on a combination of computational methods, correlations, and experimental thermal analysis techniques. The presented approach will help to focus the experimental work to the most hazardous reaction scenarios with a better understanding of the reactive system chemistry. Computational methods are used to predict reaction stoichiometries, thermodynamics, and kinetics, which then are used to exclude thermodynamically infeasible and non-hazardous reaction pathways. Computational methods included: (1) molecular group contribution methods, (2) computational quantum chemistry methods, and (3) correlations based on thermodynamic-energy relationships. The experimental techniques are used to evaluate the most energetic systems for more accurate thermodynamic and kinetics parameters, or to replace inadequate numerical methods. The Reactive System Screening Tool (RSST) and the Automatic Pressure Tracking Adiabatic Calorimeter (APTAC) were employed to evaluate the reactive systems experimentally. The RSST detected exothermic behavior and measured the overall liberated energy. The APTAC simulated near-adiabatic runaway scenarios for more accurate thermodynamic and kinetic parameters. The validity of this approach was investigated through the evaluation of potentially hazardous reactive systems, including decomposition of di-tert-butyl peroxide, copolymerization of styrene-acrylonitrile, and polymerization of 1,3-butadiene.

The nematode Caenorhabditis elegans possesses a relatively simple nervous system of only 302 neurons, but is able to perform an impressive range of complex behaviors. This dissertation aims to understand the neurobiology of behavior by quantifying, at the systems-level, the sensorimotor response to carefully controlled stimuli. Through neuronal or genetic perturbations to the system, we can begin to uncouple the behavior from the underlying circuitry. The behavior studied here is thermal nociception, an escape response designed to protect an organism from potential tissue damage or harm from noxious heat. Vertebrates and invertebrates alike possess sensory neurons called nociceptors that detect noxious stimuli and relay the stimulus information to elicit an appropriate escape response. C. elegans is known to perform a reversal or forward response when presented with noxious stimuli at the head or tail, respectively. In this work, we develop a novel thermal stimulus assay with precise spatiotemporal control of an infrared pulse that targets small regions along the worm to spatially dissect the noxious response. We comprehensively quantify the nociceptive behavior, and identify key metrics that scale with intensity, such as speed in the escape state and the probability of certain behavioral states after the stimulus. Furthermore, we have mapped the behavioral receptive field of the worm along its body, and show a previously unreported probabilistic midbody behavior distinct from the head and tail responses. Surprisingly, the worm is able to differentiate localized stimuli at the midbody that are as close as 80 microns. We identified PVD as the thermal nociceptor for the midbody response using calcium imaging, genetic ablation and laser ablation. This suggests PVD could be used as a model to study spatial discrimination at the level of a single nociceptor. This spatial specificity further extends to pharmacological perturbations of the system. In particular, the application of clinically used painkillers to the worm results in a knockdown of this nociceptive response, but does so in a spatially specific manner. These results are promising for future studies building upon the techniques developed here, as they evidentiate the use of C. elegans as a model organism to study pain.