Molecular formation and destruction processes are explored in rapidly evolving, non-equilibrium astrophysical environments. First, a semi-classical calculation is made for the rate coefficients of excited atom radiative association to form molecular hydrogen and of the process C⁺ + O → CO⁺ + hν. The latter process may be important to the formation of CO in the core of Supernova 1987A. It is shown that the excited atom process may have been important to the formation of H$\sb2$ during the early part of the epoch of recombination in the early Universe. The equations of ionization balance and molecular formation and destruction have been integrated through the epoch of recombination. Other processes are examined in detail. These include heating and cooling of the primordial plasma, damping of fluctuations prior to decoupling, and the possibility of a radiation-driven instability at the onset of recombination. A calculation is presented of the time-dependent chemical evolution in the rapidly expanding outer envelope of SN 1987A. Various cooling rates and hydrogen abundances in the envelope have been examined. It is found that large molecular abundances, in particular CO, form rapidly, while hydrogen remains mostly in its atomic forms. Near-infrared observations of the proto-planetary nebula CRL 618 are presented and discussed. Images acquired in the H and K bandpasses are consistent with a bipolar axis highly inclined to the plane of the sky. From the spectrum, a visual extinction of Aᵥ = 5.3 magnitudes to the molecular hydrogen emitting lobes is found. It is shown by comparison with spectral models that the near-infrared H₂ spectrum exhibits emission from thermally excited molecules at Tₑₓ ∼ 2000 K. A component of fluorescent emission may also be present. The suggestion is explored that large molecules, in particular polycyclic aromatic hydrocarbons (PAHs), are formed in stellar winds. It is asserted that the primary source of interstellar PAHs is mass-losing asymptotic giant branch carbon stars. It is apparent that the known numbers of the most extreme mass-losing carbon stars are able to produce PAHs in sufficient quantities to maintain an interstellar medium well mixed in such molecules at the inferred abundance.

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No description available.

Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1972.

Dissertation (Ph.D.)--Worcester Polytechnic Institute. / Keywords: nuclear physics, particle physics, phyiscs, resonance, nuyclear fragmentation, nucleon-nucleon interactions, radiation shileding, heavy-ion physics, space radiation. Includes bibliographical references (leaves 163-141).

A study of radiation damage in copper indium diselenide (CIS) is presented. The build up of extended defects and the conditions for amorphisation have been explored. In particular, dislocation loops have been characterised and the intluence of composition and temperature on amorphisation has been investigated. CIS is a candidate for high-efficiency radiation-hard solar cells for use in extraterrestrial environments.

Two new analysis methods for solar seismology are developed. Called the continuous orthonormalization (CON) and adjoint methods, their use enables both solar eigenfrequencies and eigenfrequency sensitivities (partial derivatives with respect to solar model parameters) to be computed more accurately and efficiently than with existing methods. The CON method integrates an eighth-order nonlinear system of ordinary differential equations (ODEs) which defines the linear adiabatic nonradial oscillation modes of the Sun. (The Cowling approximation is not used.) All normal modes of oscillation are treated identically, regardless of their type (pressure, gravity or fundamental) or their predominant location inside the Sun. The adjoint method integrates a related eighth-order linear inhomogeneous system of ODEs. From the resultant solution, an eigenfrequency's partial derivatives with respect to an extensive set of solar model parameters may be computed simultaneously. Extensive numerical tests confirm the validity of the two new methods. Eigenfrequencies obtained via the CON method have seven significant digits and match within 1% the eigenfrequencies obtained via finite difference or mesh approaches. (Exact agreement is neither expected nor attainable because differently defined solar models are analyzed. The CON method analyzes models which are functionally specified on a continuum of radial points; the other methods analyze models defined on discrete sets of radial points.) Eigenfrequency sensitivities obtained via the adjoint method match within 2% the results obtained by explicitly perturbing the solar model parameters and recomputing the eigenfrequencies. The usefulness and power of the two new methods are demonstrated by applying them to the solution of an elementary solar inversion problem. A sample solar model's f-mode frequencies (obtained via the CON method) are iteratively driven into agreement with an observed set of f-mode frequencies. Adjoint sensitivity results are used to alter solar model parameters within hundreds of radial bins. The frequency movement is large, comparable to the frequency separation between adjacent degree f-modes. Model changes are also large; the density near the base of the convection zone is roughly doubled, while slightly further out it is halved.

Architectural designers often need to strike an uneasy balance between idealism and reality. Under most circumstances, architects are restricted by clients, budgets, and available technologies. However, divorced from traditional constraints, visionary concepts of new dwellings, new cities, and new “worlds” will spark greater forms of innovation and drive creativity for future generations. The exploration of new spatial boundaries and conceptual environments for design will irrevocably alter the human experience while adapting new challenging roles for future architects. Architecture can be understood in part as the art of organizing spaces through the manipulation of materials and forms. Designed spaces are arranged to provide unique sensory reactions for their occupants while emotionally and physically orientating them on Earth. As a catalyst towards the awareness of one’s surroundings, architecture has always had to contend with the many limiting factors imposed by the forces on Earth. These include, but are not limited to, gravity and climate. On Earth, structurally sound construction is limited by the forces of gravity as it influences design capabilities by standardizing forms, functions, and structural elements of architectural spaces. New design challenges and opportunities arrive when we look to create structures outside of Earth’s boundaries. This thesis proposes a futuristic model of an efficient and unique passenger transport system that connects Earth-based hybrid air/space ports with an outer space orbital infrastructural hub. This modern intervention will allow for new outer space industries, such as transit, tourism, and hospitality, which will provide unique opportunities for the future of humanity. Additionally, the thesis studies the positive architectural and experiential potentials for the future living occupancy of outer space. In recognizing the financial and logistical limitations of current space constructions, such as the International Space Station, the thesis looks beyond the limitations of current technologies and towards designs that are driven by the fulfillment of human experiences in space. Life in space, the thesis envisions, will spark new human experiences and rituals while necessitating new forms and designs in architecture. Weightlessness and its related spatial disorientations, in addition to the many other unique conditions in this unfamiliar territory, will inspire a new conceptual language for architecture and human cultures. The thesis will demonstrate that spaces designed for extraterrestrial experiences can be innovatively dynamic as they respond to new cultures and activities that evolve as a reaction to extreme conditions. Introducing humans to the environs of orbital space will be the initial stage in a long-term phasing tactic to colonize and commercialize beyond the expanse of Earth, eventually extending humanity to the remote neighbouring planets of the universe.

Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references (leaf 36). Also available via the World Wide Web.

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