This thesis reports the preparation of novel multi-responsive and multiply stimulable triblock copolymers. The resultant polymers were used to coat cotton fabrics and glass to render them amphiphobic. Further, a method was developed for the preparation of poly(ethylene glycol)-block-poly(hydroxyethyl methacrylate) (PEG-b-PHEMA) via anionic polymerization. The multi-responsive copolymer refers to poly(ethylene glycol)-orthonitrobenzyl-poly[2-(perfluorooctyl)ethyl methacrylate)-block-poly(2-cinnamoloxyethyl methacrylate) (PEG-ONB-PFOEMA-b-PCEMA, or P1). P1 was synthesized via atom transfer radical polymerization (ATRP) of FOEMA and a precursory monomer of CEMA using a PEG macroinitiator. The copolymer was multi-responsive or dual light-responsive because the ONB junction cleaves and PCEMA block becomes crosslinked upon UV photolysis. The multiply stimulable copolymers are a series of poly(ethylene glycol)-disulfide-poly[2-(perfluorooctyl)ethyl methacrylate)-block-poly(2-cinnamoloxyethyl methacrylate) (PEG-S2-PFOEMA-b-PCEMA) copolymers. These polymers were synthesized by the end-coupling Py-S2-PFOEMA-b-PHEMA and PEG-SH, and subsequent cinnamation of the PHEMA block. These polymers are multiply stimulable because the S2 junction and PCEMA block respond to different stimulations, such as reducing agents and light, respectively. These synthetic strategies will advance the field of stimuli-responsive polymers by providing novel functional polymers for the generation of durable self-cleaning surfaces. The above polymers form micelles in water or water/organic solvent mixtures because of the water-soluble PEG blocks. Polymer-coated cotton was obtained by immersing cotton in micellar copolymer solutions before subsequent drying and annealing treatment. Upon photolysis, the PEG block was cleaved and the PCEMA anchoring layer became crosslinked. Such a crosslinked and stable layer was rendered amphiphobic because of the exposed PFOEMA block. A similar coating can be obtained from P2. Two types of stimulations including photolysis and reduction treatment need to be applied to yield amphiphobic textiles. This coating strategy is unique and environmentally friendly because the water- and oil-repellent coatings were prepared from an aqueous solution for the first time. In a further study, a novel and long-sought method was developed for the anionic polymerization of PEG-b-PHEMA. A PEG-DPE macroinitiator was synthesized and subsequently converted into an active initiator by reaction with sec-butyl lithium. Consequently, the active initiator underwent polymerization with HEMA-TMS to yield PEG-b-P(HEMA-TMS). Upon post-polymerization modification, PEG-b-PHEMA was obtained with a low polydispersity of 1.08. / Thesis (Ph.D, Chemistry) -- Queen's University, 2013-04-29 12:25:54.593

Due to the varied climate of devices used today, the web must accommodate to every use case via responsive design. The problem is that images are often forgotten when implementing fluid design, resulting in slower loading of pages and more data sent than necessary. This thesis aims to explore through a literary study which valid standardized responsive image solutions there are using HTML5 and how to implement them. The empirical study of this thesis will be an experiment conducted to find answers on what the benefits are and what you must consider when implementing responsive image solutions. The experiment consists of collecting data from three different websites implementing various degrees of responsive image solutions. We conclude from the literary study that there are currently two valid standardized responsive image solutions in HTML5 in the form of the ‘picture’ element and the ‘srcset’ attribute. We find that the increased size of data stored on disk and the increased complexity of the markup and images must be considered when implementing responsive image solutions. The benefits of the technique will show in terms of decreased loading times of the page and less data sent over the network. We also concluded that a clearer focus and more context was achieved on the images implementing art direction.

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There has been a long, but disparate discourse among those responsible for our built environment about the inevitability of change on the artifacts we inhabit and those social contracts that influence their making. At a basic level doors and operable windows are an indication of the various flows that move through buildings. Innumerable “passive” and “active” strategies have been devised to allow changes to building floor plans and sections, to control sunlight and wind, to change function, etc. Hundreds, or perhaps thousands, of prototypes have been proposed and developed that change shape or composition in response to various social and environmental pressures. Though not always done with the goals of sustainability in mind, these prototypes often sought to provide increased agency for users, improved energy-efficiency and cost-effectiveness, and other commonly understood goals of sustainability. A number of books, hundreds of articles, and dozens of patents beautifully illustrate many proposed and built examples from which to learn but the descriptive terms employed are greatly varied (i.e., adaptable, animated, collapsible, deployable, enabling, evolutionary, flexible, intelligent, kinetic, manipulable, mutable, open-system, portable, protean, reconfigurable, responsive, revolving, smart, and transformable, etc.) and are therefore difficult to find. By reviewing and synthesizing the existing literature, this study provides a starting point for future research that offers both insight into how these terms have been used over time and a critique of such concerns and the exclusion of the topic within sustainability rating criteria. / text

A series of well-defined stimuli responsive water soluble [60]fullerene (C₆₀) containing polymers such as polyelectrolytes (polyacids and polybases), polyampholyte and polyzwitterionic polymers were synthesized using atom transfer radical polymerization. The aqueous solution properties of these polymers with respective external stimuli such as pH, temperature and salt were studied using potentiometric and conductivity titration, light transmittance, laser light scattering and transmission electron microscopic techniques. The influence of polymer concentration, temperature, pH and electrolyte on the hydrodynamic radius (Rh), radius of gyration (Rg) and aggregation number (Nagg) of the particles were investigated in detail to elucidate the morphology of the particles. The morphology of the aggregates was further confirmed by the TEM micrographs. The cytotoxicity of the pH responsive C₆₀ containing well-defined polymers (PAA-b-C₆₀, C₆₀-b-PAA-b-C₆₀ and PEO-b-PAA-b-C₆₀) was studied to confirm the suitability of these particles as potential drug delivery vehicles. The binding interaction between the anti-cancer drug (doxorubicin) and C₆₀ containing pH responsive polymers was studied using isothermal titration calorimetry, and the implication of the results will be discussed. / Singapore-MIT Alliance (SMA)

Energy harvesting using ferrofluid in OHP. Characterization of as-synthesized (bare) and surface-modified ferrofluid samples was performed using Fourier transform infrared spectroscopy, dynamic light scattering, X-ray powder diffraction, transmission electron microscopy, and atomic force microscopy. These ferrofluids were tested in a novel oscillating heat pipe set-up was utilized to harvest electricity, demonstrating the concept of ferrofluidic induction. Cobalterrite nanoparticles surface-modified with citric acid demonstrated good magnetic strengths and generated voltages close to those of the as-synthesized ferrofluids while maintaining dispersion. Surface modification of ferrous nanoparticles with SRP. Thermo responsive polymer poly(N-isopropylacrylamide) was successfully grown from the surface of cobalt-zinc ferrite nanoparticles. A dual responsive block copolymer, pH and thermo responsive comprised of poly(itaconic) acid and poly(N-isopropylacrylamide) was successfully polymerized from the surface of ferrous oxide nanoparticles. These composite having magnetic properties along with stimulus can be used in applications such as controlled drug delivery and similar biomedical applications.

Nucleic acid amplification is responsible for pushing the limit-of-detection of molecular diagnostic assays to unprecedented levels. We developed an assay based on protein-responsive programmable dynamic DNA assembly (PRPDA) to detect proteins via an intermediate process involving nucleic acids for taking advantage of nucleic acid amplification strategies. PRPDA has previously been designed for sensitive protein analysis in fluorescent assay formats. To further push the detection limit and to achieve assay miniaturization and multiplexing, we sought to combine PRPDA with electrochemical readout. We were able to achieve LOD of 1 pM by employing wrinkled gold electrode for the PRDA protein detection scheme. Which is 2800 times improvement compare to the 2.8 nM demonstrated by fluorescent transduction. / Thesis / Master of Applied Science (MASc)

A white clover ( Trifolium repens ) system, based on one ozone-sensitive (NC-S) and one ozone-resistant (NC-R) clone, has been developed as an indicator to estimate the effects of tropospheric ozone on plant biomass production. A reduction in the vegetative biomass ratio (NC-S/NC-R) of the clones was correlated with increasing concentrations of ozone during a 28-day exposure period. However, the mechanism of ozone sensitivity or tolerance at the biochemical or molecular level is not known. Superoxide dismutase isozyme activities in the two clones did not respond differently to ozone treatment. However, catalase activity increased somewhat more in the leaf tissue of NC-R, compared to NC-S, after ozone treatment. Two-dimensional polyacrylamide gel electrophoresis (PAGE) showed the presence of two proteins (Ozone-Response-Proteins, ORPs) that were more responsive to ozone in the tolerant genotype than in the sensitive one. After ozone treatment for three days, the ORPs were four-fold higher in leaf tissue of NC-R compared to NC-S. Also, the amount of the ORPs was twenty-fold higher in leaf tissue of ozone-treated NC-R than in that of control NC-R. These proteins have apparent molecular weights of 21.5 kD and 23 kD and isoelectric points of 4.1-4.4 on SDS-PAGE gels. The filtrate of a 100 kD concentrator showed that the native molecular weights of the ORPs were less than 100 kD. The results obtained from a study of field samples demonstrated that protein content in leaf tissue of both NC-R and NC-S was positively correlated with ORP content. / Master of Science