“Wearable Metal Origami” is a research leading to a collection of wearable objects, made from metallised folding textile. The research engages with current concerns in industrialised society, where new materials and innovative products are in demand. The material I have developed is influenced by historical and contemporary jewellery and clothing as well as by deployable structures; folding patterns are based on folding patterns in nature and on the knowledge of origami mathematicians; production processes include traditional printing and jewellery techniques. Bridging all these disciplines, the outcome is a novel material that could be used in various design fields but is particularly relevant to jewellery for its striking visual character, its flexible movement which easily adjusts to the human body, and the possibility to use precious metals. I based my research in the department of Goldsmithing, Silversmithing, Metalwork and Jewellery because this department had helped me develop the initial material during my MA course, so I knew it could provide me with the necessary equipment and support in designing wearable pieces. My project was finally conducted within a departmental team research project (Deployable Adaptive Structures) in which my colleagues investigated the broader application of metallised or otherwise tessellated folded textile in such fields as interior architecture, sunscreens and water sculptures, and ways of actuating the material either virtually or by mechanical means. ““Wearable Metal Origami”?” is based on MA project work, where I had used one folding pattern and found one production method. I strongly believed that this material would be ideal for the creation of jewellery and larger wearable objects if I could expand the range of flexibly moving patterns, improve the production process of the material and develop appropriate design processes. My research set out to fulfil these requirements and prove the value of the material in the context of metalwork and jewellery and the applied arts. To expand the range of folding patterns I collected and analysed existing tessellating origami patterns. With this knowledge I created my own variations. All patterns were evaluated on their suitability for “Wearable Metal Origami” and a basic classification was made, based on their folding properties. A small selection of patterns was then tested to get an understanding of the influence of plate thickness, hinge width and hinge flexibility by making card-textile and plywood-textile models. I developed and tested new processes for the production of the metallised folding textile. These included preparatory processes (before electroforming), electroforming and various ways of treating the material after electroforming. Each process was evaluated on its practicality. To develop appropriate design processes for wearable objects of Metallised Folding Textile I ran four case studies, each with its own design brief. I set the briefs in such a way that they addressed different parts of the body and different qualities of the material, such as changing shape and flexibility. For each application an origami pattern was chosen and adjusted through a process of trial and error until it had the correct proportions and movement.

Heavy-metals exert considerable stress on the environment worldwide. This study assessed the resistance to and bioremediation of heavy-metals by selected protozoan and bacterial species in highly polluted industrial-wastewater. Specific variables (i.e. chemical oxygen demand, pH, dissolved oxygen) and the growth/dieoff- rates of test organisms were measured using standard methods. Heavy-metal removals were determined in biomass and supernatant by the Inductively Couple Plasma Optical Emission Spectrometer. A parallel experiment was performed with dead microbial cells to assess the biosorption ability of test isolates.

The objective of this study was to (1) measure the concentration of four anions (Cl-, F-, NO and SO ) and nine other elements (Al, Ba, Ca, K, Mg, Mn, Fe, Ni, and Si) in two nontraditional biopolymeric chemical stabilizers (EBCS1 and EBCS2), (2) investigate consequent environmental toxicity risk implications, and (3) create awareness regarding environmental health issues associated with metal concentration levels in enzyme-based chemical stabilizers that are now gaining widespread application in road construction and other concrete materials. Potential ecotoxicity impacts were studied on aqueous extracts of EBCS1 and EBCS2 using two thermodynamic properties models: the Pitzer–Mayorga model (calculation of the electrolyte activity coefficients) and the Millero–Pitzer model (calculation of the ionic activity coefficients). Results showed not only high concentrations of a variety of metal ions and inorganic anions, but also a significant variation between two chemical stabilizing mixtures. The mixture (EBCS2) with the lower pH value was richer in all the cationic and anionic species than (EBCS1). Sulfate ( ) concentrations were found to be higher in EBCS2 than in EBCS1. There was no correlation between electrolyte activity and presence of the ionic species, which may be linked to a possible high ionic environmental activity. The concentrations of trace metals found (Mn, Fe, and Ni) were low compared to those of earth metals (Ba, Ca, K, and Mg). The metal concentrations were higher in EBCS1 than in EBCS2. Data suggest that specific studies are needed to establish “zero” permissible metal ecotoxicity values for elements and anions in any such strong polyelectrolytic enzyme-based chemical stabilizers.

Abstract In this study, the removal of Pb(II) from aqueous solutions by tassel powder was studied and optimised. Batch experimentswere conducted on simulated solutions using tassel powder adsorbent and the effects of contact time, pH and concentration on the extent of Pb (II) removalwas studied. Equilibrium and kinetic models for Pb(II) sorption were developed by considering the effect of contact time and concentration at optimum pH 4 and fixed temperature(25 ◦C). The Freundlich model was found to describe the sorption energetics of Pb(II) on tassel more fully than the Langmuir. A maximum Pb(II) loading capacity of 333.3 mg/g on tassel was obtained. The adsorption process could be well described by both the Langmuir and Freundlich isotherms with R2 values of 0.957 and 0.972, respectively. The kinetic parameters were obtained by fitting data fromthe effect of contact time on adsorption capacity into the pseudo-first, pseudo-second-order and intra-particle diffusion equations. The kinetics of Pb(II) on tassel surface was well defined using linearity coefficients (R2) by pseudo-second-order (0.999), followed by pseudo-firstorder (0.795) and lastly intra-particle diffusion (0.6056), respectively. The developed method was then applied to environmental samples taken fromborehole waters contaminated with mine wastewater. The removal of Pb (ND-100%), Se (100%), Sr (5.41–59.0%),U(100%) and V (46.1–100%)was attained using tassel. The uptake of the metals from environmental samples was dependent on pH, ionic strength and levels of other competing species.

A b s t r a c t In this study, the removal of Pb(II) from aqueous solutions by tassel powder was studied and optimised. Batch experimentswere conducted on simulated solutions using tassel powder adsorbent and the effects of contact time, pH and concentration on the extent of Pb (II) removalwas studied. Equilibrium and kinetic models for Pb(II) sorption were developed by considering the effect of contact time and concentration at optimum pH 4 and fixed temperature(25 ◦C). The Freundlich model was found to describe the sorption energetics of Pb(II) on tassel more fully than the Langmuir. A maximum Pb(II) loading capacity of 333.3 mg/g on tassel was obtained. The adsorption process could be well described by both the Langmuir and Freundlich isotherms with R2 values of 0.957 and 0.972, respectively. The kinetic parameters were obtained by fitting data fromthe effect of contact time on adsorption capacity into the pseudo-first, pseudo-second-order and intra-particle diffusion equations. The kinetics of Pb(II) on tassel surface was well defined using linearity coefficients (R2) by pseudo-second-order (0.999), followed by pseudo-firstorder (0.795) and lastly intra-particle diffusion (0.6056), respectively. The developed method was then applied to environmental samples taken fromborehole waters contaminated with mine wastewater. The removal of Pb (ND-100%), Se (100%), Sr (5.41–59.0%),U(100%) and V (46.1–100%)was attained using tassel. The uptake of the metals from environmental samples was dependent on pH, ionic strength and levels of other competing species.

No description available.

Full X-ray structure analyses ot sixteen .etal cluster compounds of nuclearity 3 to 11 have been carried out to investigate to what extent the attached surface ligands govern the structure in the solid state and how this relates to the chemistry of the cluster in solution. The structure of the tetranuclear cluster [AgRu,(CO),(CzBut)(PPh,)] has completed a series of related clusters [MRu,(CO),(CzBut)(PPh,)] [M a Cu, Ag or Au]. This is only the second example of a complete series of Group IB cluster analogues and confirms earlier evidence that the bonds fro. gold are different in character to those trom silver and copper. The structures of the copper clusters [Cu,Ru.(~,-H),(CO)'Z{P(C6H'1)'}Z] and [Cu,Ru.(~,-H)Z (CO)tZ {P(CHMel ) l} l ] compared to the reported structure [Cu,Ru"(~J-H)z(CO)tZ(PPhl)l] indicate that the 'bulk' of the organophosphine groups is a major factor in determining the type of metal geometry adopted by this type of compound in the solid state. Comparison of the structural results obtained for the hexanuclear clusters [M,Ru,,(CO).,(PPh,),] [M a Cu or Ag] to those reported for the hydrido analogues [MlRu.(~,-H)z(CO)'l(PPh')l] have shown that small changes in the surface ligand set can have marked effects on the metal geometry in the solid state, providing further evidence that the energy differences between the various structural types are small for heteronuclear clusters containing Group IB metal atoms. The X-ray structure analyses of [AulRu.(~-H)(~,-H)(CO)ll{~-Ph,PCH=CHPPhz}] and [Au,Ru,,(~-H)(CO),,{~-PhzPCH,PPhz}(PPhJ)] have enabled the correlation of earlier structural data of related hexanuclear and heptanuclear mixed-metal clusters to account tor the marked differences between the structures of gold-ruthenium clusters with monodentate organophosphines, -compared to those with bidentate phosphine ligands. The X-ray structures ot the isomers [Os,Hz(CCHOEt)(CO).l and [Os.H,(HCCOEt) (CO),] provide a rare exaaple of cluster isomers differing only in the nature of the organo ligands. The structures of the high nuclearity hydrido clusters [Os.HZ(CO)'7- P(OMe),]' [Os7HZ (CO)u], and [Os7HZ (CO)..{MeCaCMe}] have shown nove1 metal fraaeworks, supporting previous observations that when hydrido ligands are present, osmium cluster geo.etries can often be unpredictable in the solid state. The structural characterisation of the large hydrido cluster monoanions [HsOs,o(CO),.]- and [HOs"C(CO)Z7]- have provided evidence for the presence of intersU Ual hydrido ligands. Comparison of these results to those reported for related compounds supports the view that in some cases. interstitial ligands become important in preventing surface ligand. overcrowding.

The use of XPS and AFS technique has been explored in the stLrly of the surface chemistry of a whole electrode surface (XPS) and the surface chemistry of natural pits (AFS). EDXA and to a snall extend SIMS were also used in the investigation of the individual pits. A high resolution Auger electron microscope which has an analytical resolution as snall as 0.1 .un enables a nevly formed pit of less than 2 .un in diameter to be investigated. By using a Cl/Mg ratio an attempt had been made to correlate the surface chemistry of whole electrodes exposed at different potentials in 1M MgCl2 solution to the surface chemistry of individual pits naturally produced qy means of a simulated metal to metal crevice made of cammercial stainless steels (SS316 and SS304) immersed in 1M MgCl2 solution. '!he correlation was fomd to be good and within the expected limit of the data produced by XPS and AFS. The estimated val ue of potentials of the surface of pit and its immediate vicinity was based on a theoretical model of variation of potential aromd a pit by Melville and also on the potential-current curve of the steel sample in the test sol ution. The Q/Mg ratio was shown to be useful in determining the activity of pits. In repassivated pits in the crevice mouth zone magnesiun was a dominant species relative to chlorine, this is in contrast to the pits in the central part of the crevice which were (ii) engulfed in general corrosion. Active pits in the area between the two regions have higher value of Cl./Mg ratio in their surface than that in the surface in their immediate vicinity. The role of chraniun in pitting corrosion is suggested to counter the pitting attack by the fonnation of chramiun oxide and oxy-chloride on the surface of pit. Molybdenun when present, also concentrates on the surface of pit. The type of corrosion attacks on sulphide inclusions in stainless steel depend on the copper content of the inclusions. Pitting will be likely to take place on pure MnS incl usions but not on copper enriched-MnS inclusions. The fonnation of copper sulphide is suggested to be important in reducing the amount of active species of sulphur on the corroded inclusions.

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published_or_final_version / abstract / toc / Chemistry / Doctoral / Doctor of Philosophy