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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.

Utilizing Animal Waste Amendments to Impaired Rangeland Soils to Reduce Runoff

Thomas, Diana M. 2011 May 1900 (has links)
Composted biological wastes contain vital plant nutrients that assist in plant growth as well as contain organic matter that promotes good soil conditions; both aid in rangeland restoration. Most importantly, it has the potential to restore water availability through increased infiltration and reduced runoff. In this thesis, local sources of composted dairy manure are utilized for application onto the degraded Fort Hood Western Training Grounds in central Texas in hopes to restore the rangeland for continued military training. Small scale rainfall simulations are applied two and eight months post-application of seven different agronomic rates of composted waste treatment (0, 5, 10, 15, 20, 25, and 30 y^3/acre) in order to determine changes in infiltration rates. July 2004 rainfall simulations, two months post application, indicate that composted wastes have not had sufficient time to incorporate into the soil matrix. Percent organic matter of the parent soil is the only significant variable of impact on maximum infiltration capacity. Composted waste treatments are concluded to have no effect on infiltration rates for any of the application rates in the summer rainfall simulations and are observed to exhibit very high variability in the amount of infiltration by a plot. January 2005 rainfall simulations, eight months post waste application, are observed to continue the trend of high variability across all treatment application rates. This variability is attributed to masking any potential effects from the treatment applications. Overall, this high natural variability disables the detection of potential effects of waste application treatments leading to the conclusion that composted waste applications do not affect infiltration on the Fort Hood Western Training Grounds. Runoff nutrient analysis observed nitrate-N to be well below Texas drinking water standards for all plots and phosphate to be above non-standardized values known to cause problematic algal growth. Natural rainfall events at intensities needed to generate runoff observed in this study are rare; therefore, nutrient pollution concern for local water bodies is low.

Producer responsibility for WEEE as a driver of ecodesign: Case studies of business responses to producer responsibility charges

Gottberg, Annika 11 1900 (has links)
Due to potential environmental, resource and health problems associated with waste, waste minimisation is a prioritised waste management strategy in many countries. Producer responsibility policies promote waste minimisation by stipulating separate collection and recycling of particular waste streams. In addition, a purpose of the policy is to encourage product development that reduces waste generation and improves recyclability. It is sometimes assumed that the financial responsibility assigned to producers for collection and recycling of their end-of-life products will instigate waste minimising product development in order to reduce costs. However, this view has also been contested. Following the adoption of the WEEE Directive (2002/96/EC) all EU member states have to implement producer responsibility for WEEE. Taking a qualitative multiple case study approach, this study explores company responses to the costs of existing national producer responsibility policies for WEEE in relation product development. The purpose is to inform policy-making on the effectiveness of producer responsibility charges in achieving waste minimising product development. The study comprises both large companies and SMEs in the lighting equipments sector. It also includes companies in EU member states without producer responsibility for WEEE in order to see if there are any differences in waste-minimising product design among countries and if national policies have an impact beyond national borders. Economic principles and previous research findings on ecodesign make up the analytical framework for the study. Quantitative data on cost-benefits of ecodesign and waste minimisation achievements were scarce. However, the company responses show that the costs imposed on the producers by the WEEE policy have had little effect on product development so far. The costs can generally be transferred to customers via product prices. The price increases were generally small and without any negative effects on competitiveness. Other drivers such as bans on certain substances, environmental industry product declarations, commercial advantages including direct customer demands from for instance public procurers, are more effective.

Investigations on the geo-environmental performance of rubber-soil /

Yip, Lai Yuk. January 2003 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 286-292). Also available in electronic version. Access restricted to campus users.

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.

Biconversion of cheese whey into fuels and solvents

Vaca Mier, Mabel. January 1985 (has links)
No description available.

Radionuclide transport as vapor through unsaturated fractured rock

Green, Ronald T. January 1986 (has links) (PDF)
Thesis (Ph. D. - Hydrology and Water Resources)--University of Arizona, 1986. / Includes bibliographical references (leaves 207-213).

Teollisuuden häiriöpäästöjen hallinnan kehittämishaasteet /

Wessberg, Nina. January 2007 (has links) (PDF)
Thesis (doctoral) --Tampereen yliopiston, 2007. / Includes bibliographical references (p. 178-195). Also available on the World Wide Web.

Effects of the reacting flowfield on combustion processes in a stagnation point reverse flow combustor

Gopalakrishnan, Priya. January 2008 (has links)
Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Seitzman, Jerry; Committee Member: Gaeta, Richard; Committee Member: Jagoda, Jeff; Committee Member: Neumeier, Yedidia; Committee Member: Yoda, Minami; Committee Member: Zinn, Ben.

Evaluation of organic and hydraulic loading on the performance of a roughing trickling filter tower using sessil media to treat a high strength industrial wastewater /

Pramanik, Amit, January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 94-96). Also available via the Internet.

The movement of selected waste constituents through the earthen liner of a manure holding pond

Cates, Kim Johnson. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 67-71).

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