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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.

The extraction and purification of poly-#beta#-hydroxybutyrate from Alcaligenes eutrophus

Harrison, Susan Therese Largier January 1990 (has links)
No description available.

Design and validation of an automated multiunit composting system

Pickens, Mark Everett. Vaidyanathan, Vijay Varadarajan, January 2009 (has links)
Thesis (M.S.)--University of North Texas, Dec., 2009. / Title from title page display. Includes bibliographical references.

Biodegradable plastics : feasible in Hong Kong?

Lam, Ho-ching, Dennis, 林浩正 January 2013 (has links)
Since their inception and invention, plastic materials have taken on an essential role in numerous applications within the lives of human beings for years now. Each year, the global figure for production of plastic is estimated to be more than 100 million tons. The major reason for the existence of such an enormous amount is due to plastics’ supremacy over other materials with their exceptionally useful properties. According to Hong Kong’s Environmental Protection Department, 13,458 tons of waste was disposed in Hong Kong’s landfills per day during 2011. Such an amount is very large in quantity, and it is predicted that the three strategic landfills of Hong Kong will be fully saturated in 2015-16 if the waste generation rate remains similar as present time and business as usual. Plastics made up approximately 19% of the overall composition of Hong Kong’s disposed municipal solid waste in 2011. Plastic material does not degrade efficiently, and since it has only been in production during the most current century, plastic specialists have not been able to conclude the final life span of the material before it completely degrades. Estimates for different plastic polymers range from 20 years to 400 years and above. To solve these increasingly serious environmental issues, the society has raised its demands and directed many researches into biodegradable polymers (i.e., plastics). They have now become more seriously considered as alternative solutions for conventional, non-biodegradable plastics. However, the creation of such biodegradable materials, the efficiency and cost of that creation and the true biodegradability of those materials is under much scrutiny and debate. The purpose of this study was multi-faceted. It primarily focused on (1) the status and production of biodegradable products in Hong Kong and (2) assessment of the general public’s receptiveness towards using such products. This study aimed to evaluate the above two aspects via literature review and interviews of representatives from biodegradable plastics companies in Hong Kong as well as students and general working-class citizens. This element inquired whether the general public would be willing to pay extra money to use biodegradable plastic products, and whether they thought that these products had beneficial effects towards environmental conservation and protection. Also, the general public would be asked their opinion on a duty for biodegradable products and whether they would be adverse to a policy implementation involving such a duty. A large portion of this project’s critically significant data was generated from random, systematic sampling of different people, asking them about the aforementioned monetary scenarios. Results were insightful and informative giving evident trends that represented the public’s attitude towards biodegradable plastics. Overall, the public was positively supportive of biodegradable technology, which is relatively new. Concurrently, extensive literature review was conducted to assess foreign practices and policies regarding biodegradable plastics, as well as the life-cycle of a primary biopolymer called polylactic acid. A concluding recommendation was constructed to envision the future waste management infrastructure in Hong Kong. That infrastructure could build off of the special region’s budding development of incinerators, composting facilities, waste-to-energy facilities, and sorting technologies. Then, to supplement biodegradable polymer production and post-use handling facilities, the Hong Kong SAR Government could implement strong waste management policies to motivate its society to aim for a more sustainable way of life. / published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Synthesis of polyethylene/starch hybrids using aqueous mini emulsion polymerization /

Shah, Brinda. January 2010 (has links)
Typescript. Includes bibliographical references (leaves 101-105).

Development of environmentally-friendly polymeric materials based on polylactide and poly[(butylene succinate)-co-adipate] blends.

Ojijo, Vincent Omondi. January 2013 (has links)
D. Tech. Polymer Technology. / Objectives of this work were to develop PLA/PBSA-based hybrid materials with better barrier properties, thermal stability, impact strength and at the same time, have relatively good strength and modulus. The specific objectives were: 1) To optimise PLA/PBSA blend composition for the desired blend properties. This entailed understanding of the role of specific interfacial area obtained from the morphologies of the blends in controlling the properties of the same and relate qualitatively, the phase morphologies to the properties of the PLA/PBSA blends. 2) To study the effect of annealing on the properties of PLA/PBSA blends. 3) To study the effect of organic modifiers on clay surfaces and the interlayer d-spacing of the clay on the morphology and properties of PLA/PBSA-clay composites 4) To study clay dispersion at various loadings and how it affects the crystallization of PLA and PBSA components in the blend.5) To study clay loading effect on the thermal and mechanical properties of the PLA/PBSA-clay composites. 6) To optimise the processing parameters, vis-a-vis: reaction time, coupling agent content, PLA/PBSA composition and processing sequence during in-situ reactive compatibilization of PLA/PBSA blends. 7) To improve the thermal stability and barrier properties through reactive processing of PLA/PBSA, in the presence of organoclays and a coupling agent. 8) To study the rheological properties of the blends prepared, as a function of clay content in the physically and reactively compatibilized PLA/PBSA blends.

Biodegradable polymeric delivery systems for protein subunit vaccines

Heffernan, Michael John. January 2008 (has links)
Thesis (Ph.D.)--Biomedical Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Dr. Niren Murthy; Committee Member: Dr. Carson Meredith; Committee Member: Dr. Julia Babensee; Committee Member: Dr. Mark Prausnitz; Committee Member: Dr. Ravi Bellamkonda.

Analysis and remediation of phthalate ester plasticizers and their degradation products in the aquatic environment

Mtibe, Asanda 25 February 2014 (has links)
M.Sc. (Chemistry) / Please refer to full text to view abstract

Biodegradable polymer particle formation using supercritical carbon dioxide

Lian, Zhuoyang. January 2006 (has links)
Thesis (M.Ch.E.)--University of Delaware, 2006. / Principal faculty advisor: Annette D.Shine, Dept. of Chemical Engineering. Includes bibliographical references.

Study of nano-mechanical properties of 3D scaffolds prepared from polycaprolactone and hydroxyapatite

Tyagi, Parul. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2008. / Description based on contents viewed Feb. 5, 2008; title from title screen. Includes bibliographical references (p. 65-68).

Mechanical properties and compostability of injection-moulded biodegradable compositions

Burns, Mara Georgieva. January 2008 (has links)
Thesis (M.Sc.(Chemical Engineering))--University of Pretoria, 2007. / Abstract in English. Includes bibliographical references (leaves 74-80).

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