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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.
91

A study of thin large aperture proportional counters

Gumble, Roger Steven, 1941- January 1966 (has links)
No description available.
92

Solar Energetic Particle Transport in the Heliosphere

Pei, Chunsheng January 2007 (has links)
The transport of solar energetic particles (SEPs) in the inner heliosphere is a very important issue which can affect our daily life. For example, large SEP events can lead to the failure of power grids, interrupt communications, and may participate in global climate change. The SEPS also can harm humans in space and destroy the instruments on board spacecraft. Studying the transport of SEPs also helps us understand remote regions of space which are not visible to us because there are not enough photons in those places.The interplanetary magnetic field is the medium in which solar energetic particles travel. The Parker Model of the solar wind and its successor, the Weber and Davis model, have been the dominant models of the solar wind and the interplanetary magnetic field since 1960s. In this thesis, I have reviewed these models and applied an important correction to the Weber and Davis model. Various solar wind models and their limitations are presented. Different models can affect the calculation of magnetic field direction at 1~AU by as much as about 30\%.Analysis of the onset of SEP events could be used to infer the release time of solar energetic particles and to differentiate between models of particle acceleration near the Sun. It is demonstrated that because of the nature of the stochastic heliospheric magnetic field, the path length measured along the lineof force can be shorter than that of the nominal Parker spiral. These results help to explain recent observations.A two dimensional model and a fully three dimensional numerical model for the transport of SEPs has been developed based on Parker's transport equation for the first time. ``Reservoir'' phenomenon, which means the inner heliosphere works like a reservoir for SEPs during large SEP events, and multi-spacecraft observation of peak intensities are explained by this numerical model.
93

Surface area and viscosity relationship for minerals.

Yen, Wan-Tai. January 1968 (has links)
No description available.
94

A study of some aspects of dispersive clay particle interaction /

Ludwig, Harald. January 1979 (has links)
No description available.
95

Particle behavior in flow through small bifurcations

Levine, Robert. January 1977 (has links)
No description available.
96

Phenomonological behaviour of particles in Newtonian and non-Newtonian liquids.

Bartram, Eric. January 1973 (has links)
No description available.
97

Propagators for higher spin particles

Cravey, Robin Lee 08 1900 (has links)
No description available.
98

Preparation and morphological study of composite nano-particles made of homopolymers

Wang, Nan 27 August 2008 (has links)
Composite polymer particles were made of two or more polymers. If these polymers are incompatible, the particles after polymer phase segregation exhibit complex morphologies which determine their properties and applications. Such particles may have applications in both academia and industry. In this work, polystyrene (PS)/ poly(2-cinnamoyloxyethyl methacrylate) (PCEMA) and poly(acetyloxyethyl methacrylate) (PAEMA)/PCEMA composite polymer particles are prepared by the evaporation of toluene from PS/PCEMA/toluene and PAEMA/PCEMA/toluene droplets dispersed in an aqueous solution containing surfactants. The surfactants used for the two systems are poly(glyceryl methacrylate)100-block-poly(2-cinnamoyloxyethyl methacrylate)15 (PGMA100-b-PCEMA15) and poly(glyceryl methacrylate)300-block-poly(2-cinnamoyloxyethyl methacrylate-ran-acetyloxyethyl methacrylate)37 (PGMA300-b-P(CEMA-ran-AEMA)37), respectively, for the PS/PCEMA and the PAEMA/PCEMA systems. The morphologies of the PS/PCEMA and PAEMA/PCEMA composite particles are analyzed by transmission electron microscopy (TEM), atomic force microscopy (AFM), and dynamic light scattering (DLS). The results indicate that the particles are polydisperse and of nanometer size. For the PAEMA/PCEMA particles, the preferred morphology is hemisphere, while for the PS/PCEMA system the morphology is a mixture of acorn and occluded core-shell. Based on Gibbs free energy theory, and knowing the corresponding surface tensions and interfacial tensions, the thermodynamic equilibrium morphologies for both kinds of composite particles were found. Due to the uncertainty during measurements and calculations, and the influence of kinetic factors, the theoretical predictions agreed only partially with the experimental observations. / Thesis (Master, Chemistry) -- Queen's University, 2008-08-27 12:16:37.142
99

Collection of hydrophilic and hydrophobic particles by suspended water drops

Allen, Raymond William K. January 1975 (has links)
No description available.
100

Studies in high energy particle production in nuclei.

Tang, Chi-Li. January 1970 (has links)
No description available.

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