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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Laser cooling and trapping of atoms

Cooper, Catherine J. January 1995 (has links)
No description available.
212

Interactions in low-dimensional Bose-Einstein condensates

Lee, Mark David January 2002 (has links)
No description available.
213

The synthesis of some new polymeric materials as potential additives for diesel fuel

Smith, Carole-Anne January 1993 (has links)
Wax crystal formation in diesel and related hydrocarbon fuels during cold weather is a long standing problem. Current polymeric additives to diesel fuel modify the crystal habit of the wax, in a variety of ways, to improve its performance at low temperature. These wax crystal modifiers (WCM) have to operate at low concentrations (0.01-0.1%) to make their use economical, so it is critical that their structures are optimised for the application. The objectives of this work was to synthesise, characterise and test some new polymeric additives which are anticipated to effect the crystallisation of the wax from the fuel and to prepare a model ethylene vinyl acetate (EVA) polymer to gain insights into the mode of action of the EVA co-polymers which are currently in use as WCM. Ring opening metathesis polymerisation was chosen as the method of preparation for these new polymeric additives. An introduction to wax crystallisation in diesel fuel and some proposals for the preparation of these new polymeric additives are given in Chapter 1. Chapter 2 discusses olefin metathesis and ring opening metathesis polymerisation reactions. The synthesis and characterisation of monomers and polymers are given in Chapters 3 and 4 respectively. Results from fuel tests are described in Chapter 5.
214

The evolution of the CIA's covert action mission, 1947-1963

Callanan, James D. January 1999 (has links)
The core contentions and departures of this study are that: (1) a three way delineation distinguished the basic types of operation that the CIA performed, between defensive, offensive, and preventive covert action; (2) the agency and its forerunner organisations anticipated government policy and initiated small-scale political clandestine operations during 1946 and 1947, ahead of being given official sanction for such activities; (3) the CIA's operations directorate played a more significant role as an instrument of wider strategic objectives, most notably during the Eisenhower years, than has hitherto been suggested; and (4) domestic politics had a strong impact on the development and deployment of CIA covert action, especially during the McCarthy era. Only by taking these factors into account can the early evolution of the CIA's operations directorate be fully understood.
215

Drivers and barriers of cold chain logistics in Chinese 3PL companies : A case study on two Chinese 3PL companies

Li, Zhang, Shuya, Zhou January 2013 (has links)
No description available.
216

FIELD AND LAB SCALE PERFORMANCE OF PHOSPHORUS REMOVAL IN POST-WETLAND SLAG FILTERS TREATING AQUACULTURE WASTEWATER IN COLD CLIMATES

Sansford, LAUREN 24 April 2013 (has links)
Eutrophication, caused by phosphorus and nitrogen overloading, is a global pollution problem for our fresh water lakes and streams. Regulatory bodies have developed treatment guidelines for point-source pollution to address this concern, creating a need for small and remote waste producers to develop low cost solutions for nutrient removal – in particular phosphorus. Constructed wetlands have often been implemented as a low cost alternative to treat various sources of wastewater, however, their efficiency in removing phosphorus has been questioned. Post-treatment blast furnace slag filters (known to have a high phosphorus sorption capacity) have been in operation since 2008 in Haliburton, Ontario, Canada, treating aquaculture wastewater following treatment by a constructed wetland. Phosphorus removal performance of three filters of varying configuration have been assessed: • a random packed filter, packed randomly with unsieved blast furnace slag removed only 26% of phosphorus overall and became severely clogged likely due to the presence of fines, poor flow distribution and formation of calcium carbonate precipitate; • a screen filter, designed as twenty individual filters separated by 3 inches of space to provide more uniform flow throughout removed 55% of the total phosphorus added and maintained a uniform flow throughout the study; and • an anaerobic filter, designed to be sealed from the atmosphere in an effort to prevent the formation of calcium carbonate and subsequent filter clogging, removed 19% of the total phosphorus added and revealed signs of poor flow distribution. Lab-scale flow through cells were designed to parallel the field scale studies and were operated at varying configuration, temperature and residence times to assess these factor effects on phosphorus removal. The results of this research provide a valuable contribution to research involving blast furnace slag filters for phosphorus removal. It has been demonstrated that cold temperatures reduce the slag filter’s efficiency to remove phosphorus (but cold-climate filters can still be effective in removing phosphorus), the removal of slag fines reduces the potential for slag clogging, a screen design is effective in promoting uniform flow and offsetting the effects of clogging and an optimum residence time may exist for phosphorus removal beyond which phosphorus removal is minimal. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-04-23 21:46:44.136
217

The Army before last military transformation and the impact of nuclear weapons on the US Army during the early Cold War

Kinman, Bret C. 09 1900 (has links)
Approved for Public Release, Distribution is Unlimited / This thesis analyzes the impact of nuclear weapon on the doctrine and force structure of the US Army during the Early Cold War (1947-1957). It compares these impacts with those that occurred on the US Air Force and Navy during that time. Nuclear weapons brought a new aspect to warfare. Their unprecedented economy of destructive power changed the way nations viewed warfare. For the Army, nuclear weapons presented a dual challenge. The Army faced a US security policy centered on the massive use of these weapons; the Army also struggled to understand how these weapons would be utilized on the battlefield. The nation's security policy of large scale strategic nuclear bombardment of the Soviet Union favored the Air Force and to a lesser degree the Navy. The Army viewed this policy as single minded and purposely limiting the nations options to all out nuclear war or deference to another national will. In all the Army faced an internal struggle to incorporate these weapons and an external struggle to retain a useful position within the US Defense establishment during this period. / Major, United States Army
218

Constructing a regional order Northeast Asia and the systemic constraints on Korean unification

Vance, Terence J. 12 1900 (has links)
Nowhere has the mid-20th century polarization of Northeast Asia been more evident than on the Korean Peninsula. Over the past six decades, efforts toward Korean unification have spanned the range of total warfare, covert attacks, propagandist affronts, and formal diplomacy to no avail. Amidst the talk of unification however, it seens a better understanding about the evolving nature of Korea's division is needed. Using a truly unique International Relations approach, this thesis explores the utility of Alexander Wendt's Social Theory of International Politics to address the evolving structure of Northeast Asia and its implications for Korean unification. The results of this analysis contrast with those of predominant IR theories such as Neorealism and suggest that unification is becoming less likely under structural trends. Additionally, the constructivist methodology employed here shows that while the United States will continue to play an important role in regional security, it must begin to diverge from its anachronistic Cold War defense posture to ensure future stability. By providing a deeper understanding about the macro-level structure of Northeast Asia, this these will contribute to the development of policies which will both enhance regional stability and aid in the eventual unification of the two Koreas.
219

Observable Signatures of Young Galaxies

White, S. D. M. 10 1900 (has links)
I review theoretical expectations for the probable appearance of galaxies during their formation phase, placing particular emphasis on the uncertainties in these ideas. Recent models suggest that formation may occur relatively recently, but that young galaxies are less spectacular than previously supposed. They may be analogous to recently discovered high red - shift radio galaxies, and indeed they may have been observed directly in faint galaxy counts. I summarise several other lines of evidence which suggest that galaxy formation may have been a recent process. Finally I give preliminary results from a detailed analytic study of the observable properties of young galaxies in a Cold Dark Matter universe. Predictions are given for faint galaxy counts and redshift distributions, and for the galaxy luminosity function.
220

American Protestants and U.S. Foreign Policy toward the Soviet Union during the Eisenhower Administration: Billy Graham, Reinhold Niebuhr, and G. Bromley Oxnam

Davis, Aaron K. January 1900 (has links)
Doctor of Philosophy / Department of History / Robert D. Linder / This dissertation considers American Protestant perceptions of U.S. foreign policy directed toward Soviet Union during the Dwight D. Eisenhower presidency (1953-1961). The question of what a culture dominated by Protestant denominations thought of its global adversary has not yet been sufficiently explored by scholars of either American religious history or diplomatic history. Most scholars who deal with the intersection of religion and foreign policy during the Eisenhower Administration tend to accentuate the close relationship that existed between government policy and general religious attitudes. That is to say, a general, widespread Protestant support of foreign policy objectives stands as the prevailing interpretation. Most historians conclude that America’s Protestant church leaders—preachers, pastors, and bishops—either actively supported government foreign policy objectives or sought to insert their own stances into existing policy. More recently, historians have published monographs that further explore Protestant Christianity with regard to foreign policy in the 1950s. By acknowledging the different strands of Protestant Christianity, scholars have raised significant questions that have heretofore gone unanswered. The primary question is the one that this dissertation seeks to answer—how widespread was American Protestant denunciation of communism and, simultaneously, how broad was American Protestant support for foreign policy objectives? Billy Graham, Reinhold Niebuhr, and Garfield Bromley Oxnam represent the three most prominent representatives of Protestant Christianity’s three major strands. These three acknowledged opinion makers that serve as the focus of this dissertation were not uniform in their perspectives of U.S. foreign policy, yet they all denounced communism and—to a degree—supported America’s efforts to combat the Soviet Union’s sphere of influence throughout the course of the Eisenhower Administration (1953-1961). This conclusion helps explain the tremendous perseverance of containment as a strategy by attributing its success, in part, to the large, Protestant body of supporters that continued to sustain and encourage Washington’s policies directed toward the Soviet Union.

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