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Carbon nanotubes have great strength, high conductivities, and very large aspect ratios. Their physical, mechanical, and electrical properties are unique and ideally suited for use in structural materials, nano-electronic devices, and as a conductive filler. The homogeneous incorporation of carbon nanotubes in bulk materials such as polymers is difficult to achieve. This is further complicated by the inhomogeneity of carbon nanotube samples. The desire to incorporate carbon nanotubes in a wide variety of devices has been the impetus for carbon nanotube chemistry over the last decade. This requires techniques for dispersal and processing, as well as methodologies for producing monodisperse samples. In Chapter 1, this thesis discusses the fundamental properties of carbon nanotubes and gives a brief overview of the state-of-the-art in carbon nanotube separation, dispersion, and the incorporation of carbon nanotubes in bulk polymers. Chapters 2, 3, and 4 outline our efforts in the area of bulk polymer suspensions; in polystyrene (Ch. 2) and in crosslinked polydimethylsiloxane elastomers (Ch. 3 and 4). Chapter 2 describes our efforts to gain an understanding of the factors limiting the graft density of polymers on the surface of carbon nanotubes, and our insights on the ability of polymer grafts to compatibilize carbon nanotubes with a host polymer. Chapter 3 discusses the application of the Piers-Rubinsztajn reaction as a method of functionalizing the surface of nanotubes with silanes, and crosslinking them within silicone rubbers. Chapter 4 outlines the development of a supramolecular strategy for the dispersion of carbon nanotubes within silicone elastomers using conjugated and di-block co-polymers. Lastly, Chapters 5 through 6 explore the initial stages of development of a “universal” polymer for the dispersion of carbon nanotubes based on highly reactive cyclooctyne monomer units (Ch. 5) and the precursor chemistry required to make this unit on sufficient scale (Ch. 6). / Thesis / Doctor of Philosophy (PhD)

This thesis work focused on polymer modification of silicon surface to improve its resistance to protein adsorption. Surface modification was achieved through surface-initiated atom transfer radical polymerization (SI-ATRP) grafting of poly(N,N-dimethyl amino) ethyl methacrylate (PDMAEMA). Since PDMAEMA is CO2-responsive, CO2 cleaning of the modified surface was also investigated. SI-ATRP was chosen to graft PDMAEMA brushes on silicon surface for high graft densities and its good control of polymer molecular weight and polydispersity. Surface characterization of PDMAEMA-modified silicon surfaces included hydrophilicity, layer thickness and surface chemical elemental composition. Protein adsorption experiments were carried out to evaluate the protein resistance of the modified surfaces. Albumin adsorption from single protein solution, as well as from human plasma, decreased significantly after PDMAEMA grafting, and the adsorbed amount decreased with increasing polymer chain length. The maximum decrease in adsorption of 90% relative to the unmodified silicon, was reached at a graft layer thickness of 40 nm (measured in the dry state). Protein resistance in plasma showed PDMAEMA -modified silicon provided significant resistance to most of the tested proteins. Compared to the PEO-modified surface, the PDMAEMA surface showed much greater resistance to albumin adsorption, but, surprisingly, it adsorbed relatively large amounts of vitronectin and prothrombin. Vitronectin may have been degraded in contact with PDMAEMA-modified surface. Also, it was the only surface out of the four, which adsorbed significant amounts of prothrombin. These unexpected observations indicate further investigation will be required to fully assess the protein-resistant properties of these PDMAEMA surfaces. CO2-induced protein desorption was also studied. Cleaning experiments were performed by bubbling CO2 into vials containing the protein-adsorbed PDMAEMA-modified surface after 2 h protein solution exposure. Radiolabelling of albumin showed that the CO2 cleaning effectiveness was related with the PDMAEMA thickness. It was found that a surface with graft thickness 20 nm (dry) responded more strongly to CO2 than one with 15 nm thickness. Western blotting results confirmed that CO2 contributed to protein desorption from the PDMAEMA surface. / Thesis / Master of Applied Science (MASc)

<p> Measurement of cellular carbon has been accomplished by gravimetric, titrimetric or directly measuring CO₂ produced in the combustion of organic carbon in the Carbon Analyzer Gravimetric and titrimetric methods are cumbersome, inaccurate at concentrations higher than 600mg/l. </p> <p> The purpose of this series of experiments is to find an alternative method for measuring cellular carbon. The proposed method is based in a carbon balance in which the soluble and gaseous forms of carbon are monitored. Cellular carbon is calculated by subtracting the sum of the soluble and gaseous forms of carbon from the initial total carbon found in the reactor. </p> / Thesis / Master of Engineering (MEngr)

Responsible investing has become a trend throughout financial markets. As World’s economies pledge to decrease the amount of greenhouse gas (GHG) emissions, environmental policies like carbon pricing (CP) are expected to be strengthened; the above is attributed to the effort of internalizing the environmental costs of the current economic system. In the same context where asset owners have been demanding to the private sector for greater coverage of Environmental Social Governance (ESG) issues, understanding exposure and risk to carbon taxation and emission trading schemes (ETS) could be a major driver for responsible investing. Nonetheless, it has been found that this environmental policy to price emissions, falls behind from a harmonized cost per emission across sectors and geographies. Defined and assessed through a quantitative scenario analysis on scope 1 emissions, all information on carbon pricing set the basis for the model. From an investing perspective, the results showed higher exposure for the electricity sector by 2030 and 2050; nonetheless, the riskiest sector to invest at, was shown as industry. The above is based on the current and expected carbon dependency, and the expected increase in coverage from carbon pricing mechanisms respectively. In addition, aviation, which is a sub-sector from offroad transportation, showed to be the main source for this sector´s exposure and risk. It is concluded that the research carried out is a first step from a complete analysis on CP, as scope 2 emissions need to be assessed. / Att investera ansvarsfullt är en trend som ökar stadigt genom finansmarknader i världen idag. Då flera ekonomier i världen utlovar att minska mängden utsläpp av växthusgaser i linje med vissa klimatscenarion, så förstärks miljöpolicys som koldioxidutsläppspriser i ett försök att internalisera externaliteter i dagens ekonomiska system. I kontexten av när ägare av tillgångar börjar kräva större täckning i miljö, socialt ansvar och ägarstyrning, kan exponering och risk i koldioxidutsläppsbeskattning och handel av utsläppsoptioner vara en drivande faktor i ansvarsfullt investerande. En utmaning i att prissätta utsläpp genom miljöpolicys ligger i hur separerade båda mekanismerna är från en harmoniserad kostnad per utsläpp genom olika sektorer och geografier. Definierad och utvärderad genom en kvantitativ scenarioanalys av Scope 1-utsläpp, verkade all information om koldioxidutläppspriser som grund till modellen. Från ett investeringsperspektiv visade resultaten en högre exponering för elkraftssektorn till 2030 och 2050. Emellertid påvisades även att industrisektorn har störst risk för investeringar. Detta är baserat på elkraftens nuvarande och förväntade koldioxidutsläppsberoende och den förväntade ökningen i täckning från koldioxidutsläppsprismekanismer i industrisektorn. Vidare påvisades flygindustrin, som är en sidosektor av offroad-transport, vara den huvudsakliga källan för denna sektors exponering och risk. Avslutningsvis fastställs det att denna undersökning endast är ett första steg i en komplett analys av koldioxidpriser, då Scope 2 utsläpp även bör undersökas.

A model system to calculate single-path coupling constant was devised to see if the couplings are additive in a system which has a dual-pathway. The system chosen was o-methyl-13C-benzoic acid. Because of anomalies in the data, the series was extended. Hybridization of the label appeared to have relatively little effect, and the conformation of the substituents very important.

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The increasing mandate to transition power generation from fossil fuels to renewable energy sources, combined with the growing electrification, has significantly boosted the demand for advanced energy storage. Lithium-ion battery (LIB) has dominated the market in a full spectrum of applications since its breakthrough in commercialization by Sony in 199. Nonetheless, LIB’s cost, safety, and somewhat limited energy density and material sources make it necessary to develop battery materials that use more abundant elements such as sodium, potassium, aluminum, silicon, and calcium. Yet, the realization of such alternative technologies is challenging to meet using conventional carbon materials. In this thesis, state-of-the-art energy storage devices based on three-dimensional porous carbon materials, namely laser-scribed graphene (LSG), are developed. The proposed strategies involve optimizing the synthesis process and properties of 3D carbon nanomaterials by laser irradiation due to its multifunctionality, cost-effectiveness and simplicity. We have innovatively developed doped and composite nanomaterials for sodium-ion batteries, lithium-sulfur batteries, and silicon-based lithium-ion batteries. This type of 3D graphitic carbon offers several advantages, including (1) binder-free self-supported electrode configuration, (2) high electrical and ionic conductivity, (3) hierarchical porosity, and (4) controllable composition upon laser exposure. Finally, we conclude by giving future perspectives and outlooks for developing this class of carbon materials to advance the field of batteries beyond conventional LIB technology.

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