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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.
41

Particles in the eastern Pacific ocean : their distribution and effect upon optical parameters

Carder, Kendall L. 30 September 1969 (has links)
The distribution of particles in the Eastern Pacific Ocean was investigated from 2 January to 14 February, l969, on the YALOC-69 cruise of Oregon State University. The size distributions were well fitted by the two-parameter Weibull distribution function, with a predominant number of them nearly exponential in distributional shape. Although particles smaller in diameter than 1i could not be measured, extrapolation of the Weibull distribution into the small particle range indicated the median particle diameter was smaller than 1μ. Measurements of light scattering were taken simultaneously with the particle size determinations. A linear relationship between the total particulate surface area and the volume scattering function, β(45°) was indicated, as well as between β(45°)/β(135°) and the mean particle diameter of distributions sharing a common shape parameter. Five different characteristic distributional shapes were found which typified all but a few of the distributions. No direct relationship was found between the distributional shapes and the water types encountered on the cruise. The first-order exponential shapes of the size distributions suggest that a detrital decay mechanism of the larger particles (i. e. phytoplankton) could be a dominant factor in determining the small particle end of oceanic particle distributions. / Graduation date: 1970
42

Quasi-elastic scattering of ultracold neutrons /

Kwon, Oh-Sun. January 2005 (has links)
Thesis (Ph. D.)--University of Rhode Island, 2005. / Typescript. Includes bibliographical references (leaves 135-143).
43

Radiative interactions: I. Light scattering and emission from irregular particles. II. Time dependent radiative coupling of an atmosphere-ocean system

Li, Changhui 30 October 2006 (has links)
In the first part of this dissertation, radiative interactions with single irregular particles are simulated. We first introduce the basic method and techniques of Finite- Difference Time-Domain method(FDTD), which is a powerful method to numerically solve Maxwell's equations with high accuracy. To improve the efficiency of FDTD, we also develop a parallel FDTD code. Since FDTD can simulate light scattering by arbitrary shape and compositions, we study several radiative interaction cases for single particles in an external plane parallel light source: the surface roughness effects on the scattering, electric and magnetic energy density distribution in irregular particles, and backscattered Mueller images. We also develop an innovative and accurate method to simulate the infinitesimal electric dipole radiation from inside a particle with arbitrary shape and composition. Our research and results are very important to study light scattering by irregular particles, Raman scattering and fluorescence. In the second part of the dissertation, we study radiative interactions in an atmosphere-ocean system. By using the so called Matrix operator method, not only the radiance of the radiation field, but also the polarization of the radiation field are obtained. Given the single layer information for the atmosphere, time dependent ocean surface shapes, and the ocean with no interface, the Matrix operator method couples these three layers and provides both the radiance and polarization reaching a certain detector in the time domain, which are essential for atmospheric science and oceanography. Several simple cases are studied by this method to demonstrate its accuracy and robustness. We also show the most difficulties in this method and discuss what one need to do in future research works.
44

AN ANALYSIS OF THE FLUCTUATIONS IN LASER LIGHT CAUSED BY THE MOTION OF ATMOSPHERIC SCATTERERS

MacKinnon, David John, 1944- January 1974 (has links)
No description available.
45

Light scattering properties of solid aerosol particles of NaCl and (NHb4s)b2sSOb4s

Perry, Roger Jon, 1950- January 1977 (has links)
No description available.
46

The application of Brillouin spectroscopy to solutions of macromolecules and inorganic complexes

San Filippo, Frank Ignatius 08 1900 (has links)
No description available.
47

The effect of long range interferences on the intramolecular light scattering function

Smith, Terry Edward 08 1900 (has links)
No description available.
48

Activity coefficients of binary solutions by Brillouin scattering

Lee, Ching Sheng 05 1900 (has links)
No description available.
49

Optimum illumination for machine vision using optical scatter data

Volcy, Jerry 12 1900 (has links)
No description available.
50

Copolyelectrolyte monolayers : organisation and surface wave dynamics

Brown, Andrew Simon January 1999 (has links)
The organisation and dynamic behaviour of a copolyelectrolyte monolayer is discussed A linear diblock copolymer of poly(methyl methacrylate) (PMMA) and poly(4-viny ethylpyridinium bromide) (QP4VP) has been the main focus of the study, although films of both the unquaternised copolymer, PMMA-P4VP and a PMMA homopolymei have also been examined for comparative purposes. The polymers were spread or subphases of water and potassium chloride solutions of varying concentrations to determine changes in structure and dynamics with polymer surface concentration and subphase salt concentration. Monolayer behaviour has been characterised from surface pressure isotherms and the use of Brewster angle microscopy. It has been demonstrated that the shape of the isotherm is dependent on the potassium chloride concentration of the subphase. Information on the organisation of the system has been determined by neutron reflectometry. A systematic variation in organisation occurs as both polymer surface concentration and subphase potassium chloride concentration change. The polyelectrolytic QP4VP block stretches more into the subphase with increasing surface concentration or decreasing salt concentration. The results have been compared to scaling laws for polymer brushes. Dynamic behaviour has been studied by the use of surface quasi-elastic light scattering (SQELS) and resonance between the capillary and dilational waves of the system is observed. The phenomenon of mode mixing and the application of viscoelastic models to the system have also been examined. It has been discovered that an accurate description of the surface viscoelastic properties of the system could not be obtained by the use of standard viscoelastic models. Mode mixing was not observed, even in those systems where negative dilational viscosities were found.

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