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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.

Mineralisation rates of natural organic matter in surface sediments affected by physical forces : a study of fresh- and brackish-water sediments subjected to changed redox conditions, resuspension, and advective pore water flow /

Ståhlberg, Carina, January 2006 (has links)
Licentiatavhandling (sammanfattning) Linköping : Linköpings universitet, 2006. / Härtill 2 uppsatser.

Spatial modeling in sediments /

Danielsson, Åsa, January 1900 (has links)
Diss. (sammanfattning) Linköping : Univ. / Härtill 5 uppsatser.

Estuarine suspended aggregate dynamics and characteristics /

Fugate, David C. January 2002 (has links) (PDF)
Thesis (Ph. D.)--College of William and Mary. / Typescript (photocopy). Vita. Includes bibliographical references.

Investigation of arsenic behaviour in a marine environment

Pengprecha, Paramee January 2001 (has links)
The conversion of arsenic into organoarsenic compounds is affected by the action of organisms, particularly marine organisms. These arsenic species require a suitable technique to distinguish the species and quantify their abundance. The ICP-MS coupled to either HPLC or HG-CT are the most popular techniques for arsenic species could be separated, but the limit of detection (LOD) was not satisfactory for the concentration of arsenic in natural waters and the chloride interference in the marine samples was high. While the HG-CT-ICP-MS, the LOD was sufficient to detect very low concentrations of arsenic, particularly for methylated arsenic species, and there was no chloride interference, however the inorganic arsenic in the reagents was high and only the reducible arsenic species could be detected. The transformation of organoarsenic compounds, specifically the conversion of arsenosugars by micro-organisms in sediment, was studied by analysing porewater from decaying seaweed in a mesocosm experiment. Arsenosugars degraded to DMAE further to DMAA to MMAA and finally to As(V) and As(III), but not as previously proposed to AsB, AsC and TMAO. Arsenic was released by the dissolution of manganese and iron clay particles in a pristine area but much more by anaerobic degradation in an industrial area. Arsenic was removed from the water phase to the sediment by precipitation, particularly with manganese at the surface sediment only in the pristine area but with iron in the industrial area.

A geomorphological approach to coarse bed-material movement in alluvial channels, with special reference to a small Appalachian stream.

Laronne, Jonathan B. January 1973 (has links)
No description available.

Sediment transport in a gravel-bottomed stream /

Milhous, Robert T. January 1973 (has links)
Thesis (Ph. D.)--Oregon State University, 1973. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.

Bed material routing and streambed composition in alluvial channels /

Jackson, William L. January 1980 (has links)
Thesis (Ph. D.)--Oregon State University, 1981. / Typescript (photocopy). Includes bibliographical references (leaves 153-160). Also available on the World Wide Web.

Sediment transport and channel morphology in a small mountain stream in Western Oregon /

Edwards, Richard Earl. January 1979 (has links)
Thesis (M.S.)--Oregon State University, 1980. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Bedload sediment transport and channel morphology of a southeast Alaskan stream /

Estep, Margaret A. January 1982 (has links)
Thesis (M.S.)--Oregon State University, 1983. / Typescript (photocopy). Includes bibliographical references (leaves 121-125). Also available on the World Wide Web.

On the Design of a Prototype Programmable Benthic Boundary Sediment Sampler

Tsai, Yi-Cheng 30 July 2004 (has links)
In this paper we developed an automatic sampling device which is capable of taking samples of the substrates at pre-programmed schedule and storing the samples for retrieval. For the reason that the sampler is operated in a severe ocean environment, the first design consideration is to use mechanisms and parts as simple as possible to reduce the risk of failure. Another primary concern is to make sure the design can preserve sediment securely in water. Besides, other considerations include size, weight, and functions of programmable sequential sampling. The sampling device is developed in two phases. Firstly, a device equipped with only one sampler is designed for achieving the purpose of programmable sampling. Secondly, the design will be extended to have multiple samplers to accomplish the task of sequential sampling. Six main designs are implemented in the first stage. They are the conceptual design of the grab for taking and storing sediment, the design of separation and reunion between grab and transmission mechanism, gearing design for transmitting motion of the sampler, timer and control circuit design for the lowest power consuming consideration, pressure hull design for installing a motor, batteries, and needed electric devices, and frame design for firmly supporting all instruments. The design of phase one was completed and its preliminary testing result came out successfully except that the collection chamber is not sealed securely enough. A new sample holder was designed and then successfully solved the problem of sediment sealing. According to the design of phase one, the concept design of the sequential sampling device of having 24 sample holders is presented.

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