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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.
51

Electrostatics of aerosols for inhalation

Kwok, Philip Chi Lip. January 2007 (has links)
Thesis (Ph. D.)--University of Sydney, 2007. / Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Discipline of Pharmacy, Faculty of Pharmacy. Includes bibliographical references. Also issued in print.
52

Experimental measurements of phase transition and hygroscopic growth of water-soluble organic compounds in atmospheric aerosols /

Chan, Man Nin. January 2004 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 54-62). Also available in electronic version. Access restricted to campus users.
53

Using a radiative transfer model in conjunction with UV-MFRSR irradiance data for studying aerosols in El Paso-Juarez airshed

Medina Calderon, Richard. January 2009 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
54

Studies on particle size-selective sampling of aerosols relevant for deposition in the human airways and onto the eyes

Gudmundsson, Anders. January 1995 (has links)
Thesis (doctoral)--Lund University, 1995. / Added t.p. with thesis statement inserted.
55

Studies on particle size-selective sampling of aerosols relevant for deposition in the human airways and onto the eyes

Gudmundsson, Anders. January 1995 (has links)
Thesis (doctoral)--Lund University, 1995. / Added t.p. with thesis statement inserted.
56

DETERMINATION OF THE COMPLEX REFRACTIVE INDEX OF ATMOSPHERIC AEROSOLS BY THE DIFFUSE-DIRECT TECHNIQUE: A STATISTICAL PROCEDURE

King, Michael D. January 1977 (has links)
No description available.
57

AEROSOL EFFECTS ON CLIMATE: CALCULATIONS WITH A TIME-DEPENDENT RADIATIVE-CONVECTIVE MODEL

Charlock, Thomas Peter January 1979 (has links)
No description available.
58

Determination of the occurrence of toxic trace metals at two sites in the North West Province using size of atmospheric aerosols / Amanda Bubu

Bubu, Amanda January 2012 (has links)
Thesis (M.Sc.(Physics) North-West University, Mafikeng Campus, 2012
59

Microscopic applications of holographic beam shaping and studies of optically trapped aerosols

Burnham, Daniel R. January 2009 (has links)
This thesis has two themes. Firstly, it concerns the original application of holographic beam shaping, employed through the methods associated with optical manipulation, to three microscopic fields of research. Secondly, it studies the optical trapping of aerosol droplets through experimentation and computational modelling. The aims are to not only provide an account of the work carried out but also a base for future researchers and students. Chapter 1 provides an introduction to the field of optical manipulation and the relevance of my studies. Chapter 2 outlines the construction of an optical tweezers which is the basis of advanced experimental work described in later chapters. It also overviews how optical tweezers operate and are quantified. In chapter 3 I describe how beam shaping is implemented for my investigations with a spatial light modulator and phase-only holograms. I detail the algorithms and software written before discussing their performance and finally the optimisation of the apparatus. Chapter 4 describes three original applications of beam shaping, including the trapping and coagulation of multiple aerosols, the manipulation of filamentous fungi hyphal tips and novel digital microfluidic operations using thermocapillary forces. I also lay down preliminary results for observing orbital angular acceleration using beams carrying orbital angular momentum. To study single optically trapped aerosols I use two methods. Firstly, their Brownian motion is investigated through sub diffraction limit position detection. Unique results in optical tweezers are shown with liquid droplets behaving as under-damped Brownian oscillators. Through these studies I demonstrate a new technique for sizing trapped aerosols, with significant advantages over current methods. I also show that the droplets can be be parametrically excited which can result in trap failure. Secondly, in chapter 6, I use a theoretical model to describe the forces imparted to a trapped droplet. I extend current theories to include the effects of a three medium focal region to accurately describe airborne optical traps. The work qualitatively explains the phenomena observed experimentally. The work contained here leaves much scope for future investigations, for which I provide an overview in chapter 7.
60

On the lifecycle of aerosol particles : Sources and dispersion over Scandinavia

Tunved, Peter January 2004 (has links)
<p>Aerosol particles are likely important contributors to our future climate. Further, during recent years, effects on human health arising from emissions of particulate material have gained increasing attention. In order to quantify the effect of aerosols on both climate and human health we need to better quantify the interplay between sources and sinks of aerosol particle number and mass on large spatial scales. So far long-term, regional observations of aerosol properties have been scarce, but argued necessary in order to bring the knowledge of regional and global distribution of aerosols further. In this context, regional studies of aerosol properties and aerosol dynamics are truly important areas of investigation.</p><p>This thesis is devoted to investigations of aerosol number size distribution observations performed through the course of one year encompassing observational data from five stations covering an area from southern parts of Sweden up to northern parts of Finland. This thesis tries to give a description of aerosol size distribution dynamics from both a quantitative and qualitative point of view. The thesis focuses on properties and changes in aerosol size distribution as a function of location, season, source area, transport pathways and links to various meteorological conditions.</p><p>The investigations performed in this thesis show that although the basic behaviour of the aerosol number size distribution in terms of seasonal and diurnal characteristics is similar at all stations in the measurement network, the aerosol over the Nordic countries is characterised by a typically sharp gradient in aerosol number and mass. This gradient is argued to derive from geographical locations of the stations in relation to the dominant sources and transport pathways. It is clear that the source area significantly determine the aerosol size distribution properties, but it is obvious that transport condition in terms of frequency of precipitation and cloudiness in some cases even more strongly control the evolution of the number size distribution. Aerosol dynamic processes under clear sky transport are however likewise argued to be highly important.</p><p>Southerly transport of marine air and northerly transport of air from continental sources is studied in detail under clear sky conditions by performing a pseudo-Lagrangian box model evaluation of the two type cases. Results from both modelling and observations suggest that nucleation events contribute to integral number increase during southerly transport of comparably clean marine air, while number depletion dominates the evolution of the size distribution during northerly transport. This difference is largely explained by different concentration of pre-existing aerosol surface associated with the two type cases. Mass is found to be accumulated in many of the individual transport cases studied. This mass increase was argued to be controlled by emission of organic compounds from the boreal forest. This puts the boreal forest in a central position for estimates of aerosol forcing on a regional scale.</p>

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