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Previous experimental studies have reported wave-like transport of heat in a small number of material systems, such as superfluids like helium II and crystal solids like bismuth. This phenomenon was henceforth referred to as 'second sound'. These rare observations of second sound are partly due to the challenge of obtaining accurate theoretical predictions. In this work, we use an ab-initio framework to study phonon hydrodynamics in 3D crystal fluorides and alkali hydrides, including sodium fluoride (NaF), lithium fluoride (LiF), lithium hydride (LiH), and sodium hydride (NaH). Moreover, we predict the existence of phonon hydrodynamics regime in bilayer graphene systems, including AA-bilayer graphene and AB-bilayer graphene. First, we obtain the second and third-order interatomic force constants using first-principles calculations, which are based on density functional theory (DFT). Secondly, we calculate the lattice thermal conductivity and phonon scattering rates by solving the Boltzmann transport equation (BTE). Thirdly, we apply Guyer's condition to show the phonon hydrodynamics regime based on the average Normal, Umklapp, and Boundary scattering rates. Finally, we examine the effect of different pseudopotentials on the thermal, electronic, and mechanical properties as well as the phonon hydrodynamics regime. In addition, we report the effect of isotopes on the lattice thermal conductivity and phonon hydrodynamics regime. Our calculations predict the existence of the second sound in NaF at 15 K and 8.3 mm characteristic length, consistent with previous experimental work. Based on Guyer's condition, the hydrodynamic window was determined in terms of characteristic lengths (~10² - ~10⁸ nm) and temperatures (up to ~80 K) for fluorides and alkali hydrides. On the other hand, second sound in 2D materials has been predicted to exist at much higher temperatures relative to 3D materials. We report the existence of a second sound for AA-bilayer graphene and AB-bilayer graphene above room temperature at a characteristic length of ~100 nm.

<p> The involvement of d orbitals in the coordination of sulphur in three simple sulphur compounds ls Investigated using an ab initio approach. Comparison of minimal and extended basis set results for molecular properties such as dipole moment, molecular geometry, and force constants provides a means of establishing the importance of d orbitals In sulphur compounds and probably other second row compounds. Excited states of sulphur dioxide and ozone are studied in the hope of elucidating the respective spectra on a theoretical basis. These investigations also provide initial data for the parametrization of the semi-empirical CNDO approach for second row atoms. </p> / Thesis / Master of Science (MSc)

Background: With the increased emphasis on technology-based education, in-person educational escape room puzzles are gaining popularity in higher education. In response to challenges in delivering quality education within the virtual environment, the need to expand learning opportunities within the digital environment has never been greater. Methods: The purpose of this study is to investigate nursing students’ experience using gamification Virtual Interactive Puzzle Escape Room (VIPER), which incorporates tasks of medication calculations and safe blood transfusion procedures. Using a quasi-experimental explanatory post-test design, the sample consisted of (N=52) third-year nursing students enrolled in a medical-surgical nursing course from Ottawa, Ontario. The reliable and validated GAMEX tool was used to assess the gameful experience of the VIPER. A secondary question identified if age of participants influence their gameful experience scores. Results: Participants perceived VIPER improved knowledge, skills and judgement and can be an effective educational modality to apply skills of medication calculations and reinforce the nursing skills in complex clinical interventions. Conclusions: By incorporating creative and engaging game elements into nursing education, educators can enhance the learning experience of nursing students and prepare them to provide high-quality patient care.

My research study aimed to explore the pedagogic shifts between working with concrete to more abstract conceptions of number. By using a case study approach focused on a grade 2 (G2) Foundation Phase (FP) teacher who retained her class into grade 3 (G3), I gathered data on her teaching over two years (2012-13) in the context of the ‘Lesson Starters Project’ (LSP). In addition, the teacher also participated in another project within the Wits Maths Connect Primary project (WMC-P) which was focused on developing content knowledge related to primary mathematics during 2013. Whilst content knowledge course assessment indicated gains through this year, the teacher’s results indicated gaps in mathematical content knowledge - a feature that literature has highlighted as quite common amongst primary teachers in South Africa and internationally. My focus in this study is on the extent to which this teacher in the LSP professional development project specialised content and modes of representation and showed connections between these aspects. The findings showed that there were varying degrees of specialisation of content and specialisation of representations. In other words, the teacher is seen to make the mathematics more sophisticated in conjunction with the use of a variety of representations or strategies. There was evidence that the degree of shifts towards more abstract strategies depended at least partially on the teacher’s beliefs about the abilities of different learners in her class.

xv Abstract The aim of this thesis is to investigate the accurate stabilization energy and binding free energy in various non-covalent complexes spanned from small organic molecules to biomolecules. Non-covalent interactions such as H-bonds, π...π stacking and halogen bonds are mainly responsible for understanding of most biological processes, such as small molecule interactions with surface, protein-ligand binding in the cell machinery, etc. In the thesis, different non-covalent complexes such as graphene…electron donor- acceptor complexes, DNA base pair interaction with silica surface, etc, were investigated. The reference stabilization energies were calculated at ab initio level, e.g., CCSD(T)/CBS method wherever possible. On the other hand, more approximated scaled MP2 method (MP2.5/CBS/6-31G*(0.25)) is taken as reference instead of CCSD(T)/CBS due to the size of the complexes. Further, the DFT and MM energies were also tested towards the reference one. The knowledge of non- covalent interaction is required for rationalizing of any association processes in nature which requires accurate description of the free energy change. The state-of- the-art molecular dynamics simulation in full atomic scale and biased metadynamics free energy method is used for binding free energy calculations. The well tempered...

Abstract  Purpose – The purpose of this study is to investigate if it is more efficient and effective to manufacture in North America or supply from Europe. This will be calculated with the help of a tool created by the two authors. The tool created in this study will be the basis for future strategy and manufacturing decisions in Sweden or locally in the U.S. The study will thereby answer the following research questions to fulfill its purpose:  RQ1: What costs influence the transportation between Sweden and the U.S?  RQ2: What risks influence the transportation between Sweden and the U.S?  RQ3: What is an efficient and effective strategy to implement for a supplier in order to improve costs and decrease risks?  Method – A case study was carried out by the authors at a global manufacturer plant located in Fountain Inn, South Carolina, USA. The results have been found using methods including documentation studies and semi-structured interviews collecting both qualitative and quantitative data. An analysis of the empirical data combined with the literature theories was conducted thereafter.  Findings – It was found that the freight cost and the packaging cost were the most influential costs when calculating the total cost for the whole transportation between Sweden and the U.S. Moreover, was the risk of interruption of the transport during the freight overseas seen as the most influential risk that could influence the cost of the transportation. The developed tool and the simulated scenarios indicated that it would be more efficient to manufacture in North America than transport the goods from Europe. The developed tool can be used for future strategy and manufacturing decisions in Sweden or locally in the U.S.  Implications – Depending on which scenario due to the user's input, the study’s implications can differ. However, when comparing the two alternatives, the most common outcome was consistent being to manufacture in the U.S. This would, in most scenarios, be seen as cheaper than manufacturing the articles in Sweden and then shipping all these to the U.S by freight.   Limitations – Considering the purpose of this study is to investigate if it is more efficient and effective to transport the goods from Europe or manufacture in North America. Therefore, this thesis will not consider costs related to the assembly line and manufacturing. Neither will costs associated with the environment, such as carbon dioxide emission and air pollution. This also applies to the quality cost incurred because of scarcity and other factors related to quality control. These areas are not believed to affect the tool and its calculation, as the requirements for quality and the environment are high at the case company. The focus of this study will be on sea freight by cargo ship and road by truck.  Keywords – Supply chain, Logistics, ABC-calculations, Transportation calculations, risks

In the current LHC era, a vast number of models for BSM physics are being tested. For predictions accurate enough to match experimental errors, theoretical calculations have to go beyond LO estimates. However, calculating one-loop corrections in BSM models involves many new particles with specific model dependent properties. Therefore, they are done largely by hand, or in partially–automated ways. I present a fully automated tool for the calculation of generic massive one-loop Feynman diagrams with four external particles, implemented as a module within the fully automated MadGolem framework. With this one can compute the NLO–QCD corrections to generic BSM heavy resonance production processes, for example in the context of supersymmetric theories.

NMR spectroscopy with in situ laser irradiation has been used to investigate the photo- and thermal isomerisation of eight azobenzene derivatives; diphenyldiazene (azobenzene), p-phenylazoaniline (p-aminoazobenzene), 4-(dimethylamino)azobenzene (Methyl Yellow), 4-dimethylamino-2-methylazobenzene (o-Methyl-Methyl Yellow), p-nitroazobenzene, 4-nitro-4’-dimethylaminoazobeneze (Dimethyl-nitroazobenzene), 4-(4-nitrophenylazo)aniline (Disperse Orange 3) and N-ethyl-N-(2-hydroxyethyl)-4-(4-nitrophenylazo) (Disperse Red 1). The rate constants and activation parameters of the thermal cis-to-trans isomerisation have been measured experimentally and correlated to the mechanism of isomerisation in two solvents. The experimental data show that the values of the activation energy (related to the enthalpy of activation) and the entropy of activation (related to the Arrhenius pre-exponential factor) vary significantly from molecule to molecule and thus both of these parameters influence the inter-molecule variation of the rate constant. Similarly, both of these parameters influence the solvent-dependence of the rate constant. Complementary computational studies have been carried out in the gas phase and in solution using density functional theory (DFT) to predict the structures of the cis and trans isomers and the transition state, and to explore the reaction coordinate. The theoretically predicted activation parameters are compared with those determined experimentally, and the utility of DFT calculations in predicting the effects of molecular structure and solvation on the kinetics of cis-to-trans isomerisation assessed. The DFT-predicted values of the activation energy and Gibbs free energy of activation in DMSO are in good agreement with the experimental values, while the values in benzene tend to be in less good agreement. The DFT calculations are unsuccessful at predicting the entropy of activation, where in all cases there is a large discrepancy between the theoretical and experimental values. The DFT- calculated energy differences between the activation energies of the two inversion pathways for the asymmetric azobenzenes suggests the favourable phenyl ring for inversion. The formation of a linear transition state from a dihedral rotation potential energy curve is explained in terms of the lower activation barrier of the more favourable inversion route (α-inversion) than that of the dihedral rotation pathway, and suggests the inversion through the α-phenyl ring to be the favoured pathway for substituted azobenzene. DFT calculations are able to obtain a transition state corresponding to pure rotation pathway for two azobenzene derivatives. The higher activation barrier for the formation of the transition state corresponding to this pathway compared to that of the formation of the α-transition state confirmed the previous conclusion. DFT predictions of the effect of protonation on the thermal rates of isomerisation of azobenzenes substituted with electron-donating group were in good agreement with the experimental results; both conclude faster isomerisation and lower activation barriers on protonation. However, DFT calculations could not confirm the postulation of rotational transition state for the isomerisation of the protonated molecule, as a result of weakening of the N=N bond by protonation.

Clusters constitute an intermediate state of matter between molecules and solids whose properties are size dependent and can be tailored. In recent years, cluster science has become one of the most exciting areas of research since their study can not only bridge our understanding between atoms and their bulk but also between various disciplines. In addition, clusters can serve as a source of new materials with uncommon properties. This dissertation deals with an in-depth study of clusters as a bridge across physics, chemistry, and materials science and provides a fundamental understanding of the structure-property relationships by focusing on three different topics. The first topic deals with superatoms which are clusters that mimic the chemistry of atoms. I show that superhalogens and superalkalis can be designed to mimic the chemistry of halogen and alkali atoms, respectively. An entirely new class of salts can then be synthesized by using these superatoms as the building blocks. I have also explored the possibility of designing highly electronegative species called hyperhalogens by using superhalogens as ligands or superalkalis as core and a combination of both. Another aspect of my work on superatom is to examine if traditional catalysts (namely Pd) can be replaced by clusters composed of earthabundant elements (namely Zr and O). This is accomplished by comparing the electronic structure and reactivity of Pd clusters with isoelectronic ZrO clusters. The second topic deals with a study of the electronic structure of coinage metal (Cu and Ag) clusters and see if they remain unchanged when a metal atom is replaced by an isoelectronic hydrogen atom as is the case with Au-H clusters. The third topic deals with clusters as model of polymeric materials to understand their gas storage and sequestration properties. This is accomplished by studying the trapping of H2, CO2, CH4 and SO2 molecules in borazine-linked polymers (BLPs) and benzimidazole-linked polymers (BILPs). The first two topics provide a bridge between physics and chemistry, while the third topic provides a bridge to materials science.