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In the packaging industry, cushioning products are usually made of plastic materials, such as polystyrene. The insulation and lightweight character make it more popular and convenient to use. However, the extensive use of it creates more waste leading to an environmental problem. Usually the cushioning foams are discarded after being used for inbox protection as packaging material; eventually they end up in a landfill. Most plastic foams are not biodegradable, which cannot be composted and will create more and more waste that affects the ecological system. In the mean time, foams made up of bio-degradable materials are considered. In general, biodegradable plastics are starch-based or cellulose-based, and the biodegradable components can be found in corn (e.g. corn starch, and corn cob). Instead of extracting the corn component, here popped corn kernel will be investigated for its suitability in packaging applications.

Polyvinyl Chloride (PVC), a plastic polymer composed of ∼43% hydrocarbon by weight and ~57% chlorine has become extensively used in our daily lives. However, the disposal of waste PVC plastics presents serious problems. The increased awareness of these problems requires the development of a reliable technique to dispose of these wastes in a safe and environmentally benign way that is devoid of the formation/release of organo-chlorine compounds. Chemical degradation of PVC is a technology that transforms PVC waste into completely new chemical products that don't contain chlorine. Sub-critical water (SCW) treatment is one of the most reliable technologies since SCW as a chemical reaction medium having adjustable physico-chemical properties. Hydrodechlorination (HDC), a reaction that replaces organically bound chlorine by hydrogen, can be accelerated by the presence of metal oxide catalysts (alumina supported palladium, Pd0/Al2O3) or raney nickel. When combined with SCW treatment, HDC offers a disposal process that is free from unwanted by-products. The rate of borohydride decomposition is accelerated by raney nickel. The HDC efficiency of virgin and formulated PVC in SCW under various reaction conditions of time and temperature was evaluated systematically. The time of reaction was varied from 1 to 4.5 hours and the temperature was varied from 150 to 280°C in the presence of palladium on alumina (Pd/Al2O3) or raney nickel. The efficiency of HDC varied from ~3% up to a completed dechlorination. Thus, organically bound chlorine in PVC in a water phase can be converted, virtually quantitatively, to chloride ion. / Response surface methodology (RSM) was used for experimental design and data analysis. The computer output from the Design-Expert software was used to optimize a model for the dechlorination as a function of time and temperature. A subsequent analysis of variance associated with the fitted model indicated a good fit between observed and predicted HDC efficiencies.

The importance of programming the built environment is increasingly recognized, mostly because of the growing complexity of architecture. Nevertheless, little attention has been paid to the meaning of architecture for its users. This thesis reviews the research on meaning in architecture, and proposes new directions in the investigation of meaning within the process of architectural programming.

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The present study examines the cycling of elements in the biosphere. The first chapter proposes a theoretical framework for this cycling based on both metal/ligand theory and mass balance studies. Empirical modelling serves as an alternative and complement to mass balance studies in predicting the export of elements from watersheds. Watershed output (export per unit area per unit of time) is predicted using atmospheric deposition rates, an element bonding strength index, the watershed area and a forest classification (deciduous vs coniferous). Finally the last chapter examines, in a speculative fashion, the partitioning of elements between the atmosphere and hydrosphere as a function of element behaviour and discusses the ecological consequences of human activity on this partitioning.

South Africa like many countries in the non-Western world has a long history of conflict stemming back to the spread of Colonialism. Various events through the years have contributed to the solidification of European and Western dominance over all that is "African". However the move to the new South Africa has facilitated renewed interaction and understanding through the celebration of peoples' differences. Differences which although unique have also contributed to the confused state of identity that exists. Current debate in South Africa centers greatly on the issue of "South African Identity", its existence, how it is created, and what constitutes it. South Africa's transition to the new democratic order has brought with it major shifts in the order and nature of peoples' identities as well as a "new" language that represents the collective identity of the society. This study focuses on the role of identity in architecture and examines the transformation and development of South African architectural expression and reflection as seen through the window of identity. r The study seeks to question how the built environment can begin to resp---o--nd to and reflect the concerns and aspirations of its inhabitants and also highlights the existence of the mutually constitutive link between identity, space and the built form. Key principles are set out in the study and are further examined through the critical analysis of both local and international precedents that serve to highlight the expressive nature of architecture, as well as the reflection of the multitude of influences on built form. The aim of the study is to identity existing perceptions within the built environment and in so doing begin to r analyse how these become manifest in the built form. he case study looks in particular at the area of Wentworth, situated south of Durban, and how architecture can be used to create public space which contributes to the formation of a collective and heterogeneous community identity. An identity which celebrates the diversity of its inhabitants while giving dignity and a sense of place to the environment. / Thesis (M.Arch.)-University of KwaZulu-Natal, Durban, 2007.

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