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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

The natural history of electronics /

Gabrys, Jennifer. January 2007 (has links)
Electronics involve an elaborate process of waste-making, from the mining of raw materials to the production of microchips through toxic solvents, to the eventual recycling or disposal of obsolete equipment. These processes of pollution, remainder and decay reveal other orders of materiality that have yet to enter the sense of the digital. This thesis investigates electronics through this waste and remainder. The thesis is guided by Walter Benjamin's notion of "natural history," and focuses on the dynamic, transient and poetic qualities of outmoded or "fossilized" commodities. Described here are electronic versions of such fossils, as well as the more formless residues that are sloughed off in the pursuit of technological advance. / Electronic technologies expand beyond devices and programs to an assemblage of sites and systems. Instead of a collection of outdated artifacts, this study further suggests that it is necessary not to focus solely on the abandoned electronic gadget, but also to consider the extended contexts through which electronics and electronic waste circulate. My intention here is to crack open the black box of electronics, and track their transformation to waste across a number of fields, from manufacture to disposal, and from archive to landfill, which inform the chapters below. By focusing on waste, this study is less interested in material comprehensiveness, or all that goes into electronics, and is instead more attentive toward material proliferations. In this way, I work through the "inputs and outputs" that take place not only at a material level, but also at cultural, political and economic levels. There is much more to electronics than raw materials transformed into neat gadgets that swiftly become obsolete. This study then considers electronics not from the perspective of all that is new, but rather from the perspective of all that is discarded. These discards, this study suggests, direct us toward considerations of electronics, technologies and material culture that are informed not by "upgrades," but instead by politics and poetics.
12

Political ecology and environmental justice analysis of information and communication technology

Seo, Wang-Jin. January 2010 (has links)
Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisor: John Byrne, Center for Energy and Environmental Policy . Includes bibliographical references.
13

The geography of household computer waste management the case of North Carolina /

Amankwah, Evans Kwame. January 1900 (has links) (PDF)
Thesis (M.A.)--University of North Carolina at Greensboro, 2007. / Title from PDF title page screen. Advisor: Zhi-Ju Liu; submitted to the Dept. of Geography. Includes bibliographical references (p. 83-89).
14

Electronic waste : case of microwave ovens in the UK

Dindarian, Azadeh January 2013 (has links)
Despite the extensive research carried out on waste of electrical and electronic equipment (WEEE) over the past decades, little is known about the quality of electronic products discarded and the extent to which quality affects the decisions to dispose and reuse these products as well as the impact of the current design of products for reuse and remanufacture. This information is fundamental to understand the reasons for the recent unfettered growth in electronic waste, and to propose solutions to address this problem. In this thesis, using a multi-method approach, face to face semi-structured interviews and product fault find surveys, the author investigates and reports the reasons consumers dispose of microwave ovens and the quality of the products, in particular microwave ovens, that are discarded in the United Kingdom as well as recommended design changes to original equipment manufacturers in order to facilitate reuse and increase the lifespan of such products. By collecting and testing 189 microwave ovens disposed of cosmetic imperfections, as well as electrical and mechanical defects, the results revealed that: (i) a fifth of all microwaves disposed are in perfect working condition and can be reused without any reuse process, (ii) a high percentage of the microwaves discarded have only very minor defects, (iii) almost all microwaves discarded with minor defects can be safely refurbished for re-use, (iv) very few components are responsible for most mechanical and electrical faults, (v) for most microwaves disposed of, the prices of the parts necessary for repair are a very small fraction of the average price of a new microwave. Using face to face interviews with 82 persons disposing electronic microwaves it was also found that: (i) consumers are largely unaware of alternative routes to send their end-of-life/use functional products other than the public recycling facilities, and (ii) a large proportion of the consumers disposing of microwaves intend to buy a similar product, only partially supporting the widely-held belief that e-waste is driven by a desire for the latest technology. Based on these results, the author argues that, for microwave ovens disposed in the United Kingdom via household waste recycling centres, the quality of the products discarded is not a serious impediment for reuse, neither are the prices of spare parts. Furthermore, the major factor preventing reuse is the current design of this product, which makes remanufacturing difficult and onerous, as well as the receptiveness of the market for second hand items. Using this information, the author also proposes small changes in design that can significantly improve reusability and, as a consequence, increases the life span of these products.
15

The natural history of electronics /

Gabrys, Jennifer. January 2007 (has links)
No description available.
16

Informal Electronic Waste Recycling: Metal Concentrations in Pregnant Women and Neonates and Associations with Adverse Birth Outcomes in Guiyu, China

Kim, Stephani S. 12 December 2017 (has links)
No description available.
17

Assessment of environmental and public health hazards of electronic waste

Fitzwater, Kendra K. January 2007 (has links)
Electronic waste or `e-waste' is a rapidly growing form of solid waste worldwide. The heavy metals present in various electronic components demand attention because such metals may leach and pose significant health and environmental hazards (U.S. EPA, 2007). Knowledge of the potential of heavy metal leaching from e-waste represents an important contribution for developing U.S. standards for classifying e-waste as hazardous waste. Hazardous elements which leach from a variety of electronics wastes were assessed in laboratory batch studies. Electronic components evaluated included PC cathode ray tubes, PC motherboards, PC mice, television remote controls, and cellular phones. Each component was disassembled and digested using the Toxicity Characteristic Leaching Procedure (TCLP), EPA Method 1312, Method EA NEN 7371 (Dutch Environmental Agency), and Method DEV-S4 (Germany). The extracts were analyzed for lead, cadmium, chromium, silver, and cobalt. The TCLP consistently leached the greatest amounts of all metals; TCLP-soluble lead was extracted well beyond federal limits for several electronic devices. / Department of Natural Resources and Environmental Management
18

Gold recovery from waste mobile phones PCBs using ammonia thiosulphate leaching and copper cementation process

Nchabeleng, Ramphagane Frank January 2018 (has links)
Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018. / The rate of waste electrical and electronic equipment (WEEE) is growing at an alarming rate, especially in countries where markets are saturated with huge quantities of new electronic goods. Printed circuit boards (PCBs) are a substantial portion of the value contained in waste from WEEE although they are only 6% of the total weight. It is reported that WEEE is currently the fastest growing waste stream in South Africa as the general population’s access to electronic goods in the last decade has increased, especially access to mobile phones. PCBs are found in any piece of electrical or electronic equipment and consist of various metals including precious metals such as gold (Au), silver (Ag) and palladium (Pd). It is reported that gold has the highest economic incentive at 15,200 $ per ton of PCBs. The rapid introduction of new and advanced technology into mobile phones has caused mobile phones to have a relatively short life span, 1 to 2 years to be exact. Mobile phones printed circuit boards (MPPCBs) have more Au content compared to computer circuit boards. They contain 350 g/ton Au whereas computer (PC) PCBs contains 250 g/ton. This research project will recover gold from waste mobile phones PCBs pregnant ammonia thiosulphate leach solution using copper cementation. The cementation process is preferred to all the other technologies of metals extraction from solution due to ultrahigh purity metals that can be obtained and to the less consumption of materials and energy. Electronic parts on the PCBs were manually removed using pliers and screwdrivers. PCBs were then cut to smaller pieces of about 2 x 2 m. The pieces were crushed and milled respectively. Some of the particles were recycled back to the crusher to get finer particles. The particles were separated to particles of sizes between 0 and 1350 μm using a shaker. The comminuted fractions of the PCBs were then used in the leaching step. Batch cementation experiments were performed by bubbling N2 in glass reaction vessel with a working volume of 0.5 L. The reactor was connected to a circulating water bath for temperature control. The recovery percentage of gold at various temperatures, agitation speeds and different amounts of copper powder used, was determined while pH was monitored. The temperature was varied at 30 °C, 40 °C, and 50 °C and the agitation speeds at 300 RPM and 900 RPM. Copper powder was added at 0.5 g/L, 1 g/L, and 1.5 g/L. Gold concentrations were measured by atomic adsorption spectrophotometer (AAS). Scanning electron microscope (SEM) and Energy-dispersive x-ray spectrometry (EDS) analyses of the copper powder after cementation (precipitates) were used to determine the surface morphology and to evaluate the quantitative aspect of the precipitate. It was found that the recovery of gold from ammonia thiosulphate leach solution was greatly affected by agitation speed. At an agitation speed of 900 rpm, 40 °C and 0.5 g of Copper powder, 96% of the gold was recovered from the leach solution. The cementation rate increased as temperature was elevated from 30 to 40 °C, but slightly decreased as the temperature reached 50 °C. The change in experimental conditions affected the gold concentration on the precipitate recovered. This study will provide a possible solution to the WEEE problem and more specifically mobile cell phones, in South Africa.
19

Human exposure and health risk assessment of polychlorinated biphenyls at two major electronic-waste recycling sites in China

Xing, Guanhua 01 January 2008 (has links)
No description available.
20

International environmental non-governmental organizations in local politics: comparing the different structures of greenpeace networks in solid toxic waste campaign in the Philippines and China.

January 2009 (has links)
Wong, Wai Man Natalie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 120-128). / Abstract also in Chinese. / Notes --- p.vii / Lists of Figures and Tables --- p.viii / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background of the Study - Transboundary movement of electronic waste (e-waste) --- p.1 / Chapter 1.2 --- Definition of Structure of NGOs Networks --- p.8 / Chapter 1.3 --- Transnational Advocacy Networks (TANs) --- p.11 / Chapter 1.3.1 --- Variables in TANs --- p.12 / Chapter 1.4 --- Organization of this Study --- p.18 / Chapter 1.5 --- Methodology --- p.18 / Chapter CHAPTER 2 --- REVIEWING TRANSNATIONAL ADVOCACY NETWORKS IN TRANSNATIONAL ACTIVISM --- p.20 / Chapter 2.1 --- Overview: Expansion of INGOs --- p.20 / Chapter 2.1.1 --- Debates: State-centric vs. Non State-centric in World Politics --- p.22 / Chapter 2.2 --- Transnational Activism in World Politics --- p.25 / Chapter 2.3 --- Networks in Transnational Activisms --- p.28 / Chapter 2.3.1 --- Linkages in Transnational Activism between the North and the South --- p.30 / Chapter 2.3.2 --- NGOs Networking: Two Levels Analysis --- p.32 / Chapter 2.4 --- TANs in Transnational Activisms --- p.34 / Chapter 2.5 --- Transnational Activism in Asia --- p.43 / Chapter CHAPTER 3 --- WHAT HAS THE GREENPEACE DONE IN ANTI TOXIC E-WASTE CAMPAGINS IN CHINA AND THE PHILIPPINES? --- p.49 / Chapter 3.1 --- Problems of e-waste --- p.49 / Chapter 3.2 --- The Greenpeace China in Anti-toxic e-waste Campaign --- p.54 / Chapter 3.3 --- The Greenpeace Philippines in Anti-toxic e-waste Campaign --- p.64 / Chapter CHAPTER 4 --- COMPARISON OF THE STRUCTURE OF GREENPEACE NETWORKS IN CHINA AND THE PHILIPPINES --- p.76 / Chapter 4.1 --- History of INGOs in China and the Philippines --- p.76 / Chapter 4.1.1 --- History of INGOs in China --- p.76 / Chapter 4.1.2 --- History of INGOs in the Philippines --- p.79 / Chapter 4.2 --- Greenpeace - National Government Relationship --- p.92 / Chapter 4.3 --- Greenpeace - Local Governments Relationship --- p.95 / Chapter 4.4 --- Greenpeace - Local NGOs Relationship --- p.96 / Chapter 4.5 --- Greenpeace - Others INGOs and Greenpeace International Relationship --- p.101 / Chapter 4.6 --- Unique factor: “Clan´ح in the operation of TANs --- p.105 / Chapter CHAPTER 5 --- CONCLUSION --- p.108 / Appendixes --- p.118 / Bibliography --- p.120

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