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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.
131

Heavy metals in urban street surface sediments

Warren, Robert Stephen January 1987 (has links)
A literature survey has been undertaken of the sources, levels and effects of heavy metal pollution in the urban street environment. Established techniques for the determination of heavy metal levels in urban dusts have been reviewed, and appropriate methods selected for use in the research project. Spatial and temporal variations of Cd, Cu, Pb and Zn in street dust have been investigated at a number sites. Metal loadings showed stronger spatial variation than concentrations with the greatest metal loadings occurring in the gutters and kerbsides. The results have been assessed in terms of surface type and condition, traffic loadings and antecedent weather conditions. The chemical associations of heavy metals in street dust, and their relationships to particle size have been investigated. Lead and Zn were associated mainly with carbonates and Fe-Mn oxides, whereas Cu is largely found in the organic fraction. Cadmium shows the greatest affinity for the exchangeable phase, and is therefore considered the most environmentally mobile metal studied. In addition to the studies mentioned above levels and chemical associations of heavy metals In school playground dust contaminated by paint flakes have been investigated. The levels of Pb were much higher than those previously reported. Exchangeable Pb concentrations represented a significant hazard to children playing in the area. In addition to the studies mentioned above levels and chemical associations of heavy metals In school playground dust contaminated by paint flakes have been investigated. The levels of Pb were much higher than those previously reported. Exchangeable Pb concentrations represented a significant hazard to children playing in the area. The final stage of the research project involved the operation of a sampling network to establish a mass balance for Cd, Cu, Pb and Zn within a residential urban street. Metal levels in atmospheric deposition, street sediments and runoff were monitored over an eight week period. Stormwater runoff was found to remove only a minor fraction of the metal deposited in the catchment during the sampling period.
132

National Promotion of Western Roads and Canals, 1785-1830

Hoffmann, John R. 08 1900 (has links)
This thesis discusses the development of roads and canals as a means of transportation and communication in the years following the Revolutionary War.
133

Veřejnoprávní úprava pozemních komunikací / Public Law Regulation of Highways

Tomáš, Radek January 2013 (has links)
RÉSUMÉ This thesis deals with the public law regulation of roads in Czech law. It explains how roads are categorised into the four legal types (motorway, main road, local road and service road) and what the criteria for the categorisation of roads are according to the Road Traffic Act - the main law governing the legal aspects of roads. The thesis also provides a demonstrative overview of other acts, regulations and technical norms governing roads in the Czech Republic. On the basis of applicable case law, the thesis deals in detail with the coming into existence of individual types of roads and with the cessation of the existence thereof. This thesis deliberately does not deal with the construction of roads and the structure of the relevant administrative bodies and their administrative procedural powers as this is beyond the scope hereof. Other topics, which are also related to the topic of this thesis, have been described in the relevant chapters only to the extent which was considered necessary for the reader's understanding of the main topics of the chapters. An important part of this thesis is the chapter on the ownership of roads, which partially overlaps into the sphere of private law. Statutory road ownership rules are explained and their overview is given in a synoptic table. The case law of the...
134

A study of the township and county unit systems of roads in Kansas as they affect the tax burden on agriculture

Harrison, Marshal Benton January 2011 (has links)
Typescript, etc.
135

宋代泉州及其內陸交通硏究. / Song dai Quanzhou ji qi nei lu jiao tong yan jiu.

January 1979 (has links)
蘇基朗. / 論文(哲學碩士)--香港中文大學, 1979. / Photocopy of manuscript. / Includes bibliographical references (leaves 242-264). / Su Jilang. / Thesis (M.Phil.)--Xianggang Zhong wen da xue, 1979. / 引言 --- p.1 / Chapter 上编 --- 宋代泉州城狀況 --- p.13 / Chapter 第一章 --- 城廓建置考 --- p.15 / Chapter 第二章 --- 重要建築物位置考 --- p.23 / Chapter 第三章 --- 坊居之區劃 --- p.34 / Chapter 第四章 --- 河渠概述 --- p.51 / Chapter 第五章 --- 橋道概述 --- p.65 / Chapter 第六章 --- 外港之分佈 --- p.75 / Chapter 第七章 --- 泉州商業中心區之研究 --- p.85 / Chapter 下编 --- 宋代泉州內通浙贛粤驛道考    --- p.130 / Chapter 第一章 --- 福泉漳沿海綫及其延長綫  --- p.133 / Chapter 第二章 --- 泉延綫          --- p.161 / Chapter 第三章 --- 延浙綫          --- p.185 / Chapter 第四章 --- 延贛綫          --- p.202 / Chapter 第五章 --- 泉汀入贛綫        --- p.213 / Chapter 第六章 --- 泉州內陸交通驛程總述   --- p.223 / 參考書目 --- p.242 / 附´圖´ؤؤ萬曆泉州府泉郡總圖 / 乾隆晉江縣志晉江縣疆域圖 / 宋代泉州城坊示意圖 / 宋代泉州近郊示意圖 / 宋代泉州內陸交通圖
136

Experimental study of factors influencing corrugation of earth roads.

Taylor-Lewis, Silranus Abosedé. January 1969 (has links)
No description available.
137

Effects of roadway geometric features on run-off-road crashes on the Florida State Highway System

Gonzalez, Javier S., January 2004 (has links)
Thesis (Ph. D.)--Florida International University, 2004. / Vita. Includes bibliographical references (p. 116-119). Also available online via the Florida International University website (http://digitalcommons.fiu.edu/).
138

Development of practical implementation methods for road pricing /

Xu, Wei. January 2006 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves [188]-195). Also available in electronic version.
139

Measurement of mixing efficiency in pavement recycling /

Lee, Teh-Chang. January 1982 (has links)
Thesis (Ph. D.)--University of Washington, 1982. / Vita. Includes bibliographical references.
140

Development of a large-scale traffic simulation model for hurricane evacuation a case study of Virginia's Hampton Roads region /

Sharma, Siddharth, January 2008 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 22, 2008) Includes bibliographical references.

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