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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.
11

Some geologic factors relating to the laboratory examination of recent sediments

Toombs, Ralph Belmore January 1953 (has links)
In selecting suitable procedures for the laboratory investigation of recent sediments, the first step suggested is that of examining conditions in the geologic environment that influence sediment properties. This step is illustrated by reference to the geologic history and physical features of a British Columbia fiord as a basis for assessing environmental conditions affecting the fiord sediments. Having inquired into the conditions surrounding the origin of sediments, the laboratory investigator is better prepared to emphasize those procedures which will provide the most significant types of data. In this project, a number of properties of recent sediments are investigated by physical, chemical and mechanical analyses, by the binocular, petrographic and electron microscopes, and by X-ray diffraction, spectroscopy, and differential thermal analysis; techniques are selected on the basis of a study of the fundamental geologic principles relating to each sediment property. A number of statistical devices are employed in the presentation of data. Illustration is given of the utility of geologic data, as obtained in the laboratory, to investigators in the fields of soil mechanics, pedology and ceramics. The sediments examined during this study were obtained as bottom and core samples from Bute Inlet. They are best described as "rock flour": the sand fraction does not exceed 5% and the minerals are relatively unaltered; the clay-size fraction averages 23% but there is no discernible clay mineral content. Mineralogically the sediments can be related, to a certain degree, to drainage basin geology. Information obtained to date on the Bute Inlet sedimentary environment suggests that sediments accumulating there are not characteristic of those which might be classified as source beds for petroleum. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
12

The scintigraphic assessment of drug delivery from dry powder inhalers

Pitcairn, Gary Roy January 1997 (has links)
No description available.
13

Mechanism of ceramic deposition by aerosol deposition method / エアロゾルデポジション法によるセラミック成膜メカニズム

Naoe, Kazuaki 24 September 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19307号 / 工博第4104号 / 新制||工||1633(附属図書館) / 32309 / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 田中 功, 教授 中村 裕之, 教授 邑瀬 邦明 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
14

Quantification of atmospheric water soluble inorganic and organic nitrogen

Benítez, Juan Manuel González January 2010 (has links)
The key aims of this project were: (i) investigation of atmospheric nitrogen deposition, focused on discrimination between bulk, wet and dry deposition, and between particulate matter and gas phase, (ii) accurate quantification of the contributions of dissolved organic and inorganic nitrogen to each type of deposition, and (iii) exploration of the origin and potential sources of atmospheric water soluble organic nitrogen (WSON). This project was particularly focused on the WSON fraction because, despite it being a potentially important source of bioavailable reactive nitrogen, a number of questions regarding its deposition mechanism (wet vs. dry), composition and origin (natural, anthropogenic or mixed) remain unanswered. There are two major difficulties in WSON determination: (i) the diversity of organic nitrogen compounds compared with the inorganic forms, and (ii) the lack of a direct determination method: the derivation of organic nitrogen concentrations in an aqueous sample involves the determination of the dissolved inorganic nitrogen (DIN) species concentration, comprising nitrate and ammonium, the determination of the total dissolved nitrogen (TDN) concentration, and the subtraction of the DIN concentrations from the TDN concentration. TDN determination requires a preparatory digestion step: high-temperature catalytic oxidation was the method used in this study. Ion chromatography (IC) was the method of choice for nitrate determination, whilst ammonium determination was by IC for rain samples, and by flow injection analysis for air samples collected into aqueous media. This thesis is structured in 3 main parts: the first part examines weekly rain data over a period of 22 months from June 2005 to March 2007 collected in 2 types of rain collector (bulk deposition and “dry+wet” deposition) located in a semi-rural area 15 km southwest of Edinburgh, UK (N55°51′44″, W3°12′19″). Bulk deposition collectors were the standard rain gauges used in the UK national network for monitoring precipitation composition. “Dry+wet” deposition collectors were flushing rain gauges equipped with a rain detector, a spray nozzle, a 2-way valve and two independent bottles to collect funnel washings (dry deposition) and true wet deposition. A key objective in this part of the work was the accurate quantification of inorganic and organic water-soluble nitrogen species contribution to each type of deposition. On average, for the 27 weekly samples with 3 valid replicates for the 2 types of collectors, DON represented 23% of the TDN in bulk deposition. Dry deposition of particles and gas on the funnel surface, rather than rain, contributed over half of all N-containing species (inorganic and organic). Some discrepancies were found between bulk and flushing rain gauges, for deposition of both TDN and DON, suggesting biological conversion and loss of inorganic N in the flushing samplers. The second stage of this project was the investigation of in situ atmospheric concentrations of WSN species, both organic and inorganic. Simultaneous daily measurements of ammonium, nitrate and WSON were made between July and November 2008 at the same semi-rural site in south-east Scotland. Discrimination between material from the gas and particle phases was achieved by means of Cofer scrubbers and PTFE membrane filters, respectively. Average concentrations of NH3 (determined as NH4+), NO2/HNO3 (determined as NO3-) and WSON in the gas phase were 82 ± 54 nmol N m-3, 2.6 ± 2.5 nmol N m-3 and 18 ± 12 nmol N m-3 respectively, and in the particle phase were 20 ± 24 nmol N m-3, 10 ± 9 nmol N m-3 and 8 ± 7 nmol N m-3 respectively (± represent standard deviation across all valid daily samples, not error of triplicate samples). Except for oxidised inorganic N, average concentrations in the gas phase were larger than in the particle phase. No evidence of solely agricultural or solely combustion sources of WSON was found, as no correlation in either phase between WSON and either NH4+ or NO3- could be established. The final stage of this project was to gain a broader picture of nitrogen deposition across Europe. Rain samples were analysed for TDN and DIN from a network of 21 different sampling locations, from the south of Portugal to the north of Finland. The average DON contribution across the 21 sampling sites was ~ 19% and, according to the data gathered in this study, DON species appeared largely unrelated specifically to agricultural or to combustion nitrogen sources, although the results varied widely from site to site. Overall, this work has shown that ON and its deposition comprises a significant component of total atmospheric reactive nitrogen.
15

Surface and Interfacial Studies of Metal-Organic Chemical Vapor Deposition of Copper

Nuesca, Guillermo M. 12 1900 (has links)
The nucleation and successful growth of copper (Cu) thin films on diffusion barrier/adhesion promoter substrates during metal-organic chemical vapor deposition (MOCVD) are strongly dependent on the initial Cu precursor-substrate chemistry and surface conditions such as organic contamination and oxidation. This research focuses on the interactions of bis(1,1,1,5,5,5-hexafluoroacetylacetonato)copper(II), [Cu(hfac)2], with polycrystalline tantalum (Ta) and polycrystalline as well as epitaxial titanium nitride (TiN) substrates during Cu MOCVD, under ultra-high vacuum (UHV) conditions and low substrate temperatures (T < 500 K). The results obtained from X-ray photoelectron spectroscopy (XPS), Auger Electron Spectroscopy (AES) and Temperature Programmed Desorption (TPD) measurements indicate substantial differences in the chemical reaction pathways of metallic Cu formation from Cu(hfac)2 on TiN versus Ta surfaces.
16

Coupling between atmospheric deposition and oceanic flux of Fe and Al in the Sargasso Sea

Tian, Zhenglong. January 2007 (has links)
Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: Thomas M. Church, College of Marine and Earth Studies. Includes bibliographical references.
17

Legacy sediments in southeastern United States coastal plain streams

Casarim, Felipe M.. Lockaby, Bruce Graeme. January 2009 (has links)
Thesis--Auburn University, 2009. / Abstract. Includes bibliographic references.
18

The oceanographic influence of sedimentation on the continental shelf : a numerical comparison between tropical and Antarctic environments /

Hemer, Mark A. January 2003 (has links)
Thesis (Ph.D.)--University of Tasmania, 2003. / Includes bibliographical references.
19

Correlation of alluvial lenses along the Kansas River between Topeka and Ogden, Kansas

Seiler, Charles Dwinnell January 2011 (has links)
Typescript, etc. / Digitized by Kansas State University Libraries
20

Modelling the inputs and impacts of nitrogen to woodland ecosystems

Hargreaves, Paul Robert January 2003 (has links)
No description available.

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