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Smart technology has become very extensive and popular in many areas of our lives in the last few years. Their role is to make life and activities performed by the user easier, faster, better and more interesting. Smart technology has been used for years in areas such as education, industry and transport. The response of the hospitality industry is to implement technology in hotels, usually the more luxurious ones, that improves the operation of employees and is a convenience for hotel guests. The name of this concept is a smart hotel, which is similar to the already existing smart house and smart city concepts. The purpose of the study was to examine the concept of smart hotel and investigate the impact that smart technology has on guests’ satisfaction, privacy and service quality. The study was conducted using mixed methods research whereby both qualitative and quantitative data were collected in parallel, analyzed individually and then linked with each other. Qualitative data collection constituted of in-dept interviews with hotel employees and hotel guests, and the quantitative part of the study was based on the online survey with hotel guests. The main findings are a proposal definition of a smart hotel, and the belief that smart technology contributes to a better quality of provided services by employees and increases the grade of satisfaction among guests. However, the result also shows that a greater role of hotels is needed in order to reduce the disproportion of equal access to smart technology for all hotel guests.

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Das Ziel dieser Arbeit war die Synthese eindimensionaler Nanoröhren basierend auf leichten Elementen. Inspiriert von Kohlenstoff Nanoröhren werden Interessante Eigenschafte für diese Materialien erwartet. Aktuell ist die Synthese solcher Kohlenstoff Nanorohren nur mit vergleichsweise aufwendigen Methoden möglich. Hierbei stellt besonders die uniforme Synthese von Röhren mit exakt gleichen Durchmessern und Symmetrien ein noch ungelöstes Problem dar. Durch diese Arbeit erhofften wir uns eine völlig neue Arte der Synthese für solche 1D Nanomaterialien zu etablieren. Dazu wurden in Kapitel 2 und 3 zwei verschiedene Typen von gespannten aromatischen Makrozyklen synthetisiert. Die synthetisierten Makrozyklen zeichnen sich durch einen hohen Grad an Funktionalisierung aus, welcher zukünftig dazu genutzt werden soll die Prinzipien der dynamisch kovalenten Chemie in der finalen Materialsynthese anzuwenden. Der durch die Funktionalisierung erzeugte innere Hohlraum dieser zyklischen Verbindungen lässt sich nutzen, um verschiedene molekulare Gäste zu binden. Die Erkenntnisse in Bezug auf die Synthese solcher Makrozyklen, die hierbei erzielt wurden, werden entscheidend dazu beitragen, dass anfänglich beschriebene Ziel der nasschemischen Synthese 1D organischer Nanoröhren in Zukunft zu erreichen. Die Methoden, der Makrozyklisierung sollten in Kapitel 4 dazu genutzt werden einen chiralen aromatischen Makrozyklus auf Basis von [5]Helicen-Untereinheiten zu synthetisieren, allerdings ohne Erfolg. Stattdessen wurde ein Nebenprodukt isoliert, dass sich als bisher unbekannter molekulare Schalter erwies. Dieser Schalter erlaubt es durch Bestrahlung bei tiefen Temperaturen reversibel ein paramagnetisches Isomer zu erzeugen. Dadurch eröffnet sich eine völlig neue Klasse an molekularen Schaltern, deren Anwendungspotential den Rahmen dieser Arbeit überschreitet. / The aim of this work was the synthesis of one-dimensional nanotubes based on light elements. Inspired by carbon nanotubes, interesting properties for these materials are expected. Currently, the synthesis of such carbon nanotubes is only possible with comparatively complex methods. Especially the uniform synthesis of tubes with exactly the same diameters and symmetries is still an unsolved problem. Through this work we hoped to establish a completely new way of synthesis for such 1D nanomaterials. To this end, two different types of strained aromatic macrocycles were synthesized in Chapters 2 and 3. The synthesized macrocycles are characterized by a high degree of functionalization, which will be used in the future to apply the principles of dynamic covalent chemistry in the final material synthesis. The internal cavity of these cyclic compounds created by functionalization can be used to bind various molecular guests. The knowledge regarding the synthesis of such macrocycles obtained here will be instrumental in achieving the initially described goal of wet chemical synthesis of 1D organic nanotubes in the future. The methods of macrocyclization were to be used in Chapter 4 to synthesize a chiral aromatic macrocycle based on [5]helicene subunits, but without success. Instead, a byproduct was isolated that proved to be a previously unknown molecular switch. This switch allows reversible generation of a paramagnetic isomer by irradiation at low temperatures. This opens up a completely new class of molecular switches whose potential applications are beyond the scope of this work.

The convergence of supramolecular and polymer sciences has led to the construction of analogs of traditional covalently-constructed polymeric structures and architectures by supramolecular methods. Host-guest complexations of polymers are also possible through well-defined synthesis of polymeric building blocks, for novel supramolecular polymers. Monotopic polymeric building blocks were synthesized by controlled radical polymerizations with a crown or paraquat initiator. The combinations of terminal and central functionalities of host and guest polymeric building blocks provided chain-extended and tri-armed homopolymers, and diblock and tri-armed copolymers. A supramolecular graft copolymer was formed from a main-chain poly(ester crown ether) and a paraquat terminated polystyrene. This comb-like copolymer was characterized by a large viscosity increase. A four-armed polystyrene-b-poly(n-butyl methacrylate) was synthesized from a pseudorotaxane macroinitiator derived from a complex of a crown-centered polystyrene and a dufunctional paraquat compound. A single peak with higher molecular weight from size exclusion chromatography proved the copolymer formation. Supramolecular interactions enhance the ionic conductivity of semi-crystalline ionic polymers; the ionic conductivity of a C₆-polyviologen and dibenzo-30-crown-10 mixture was 100 times higher than the polyviologen itself. However, ionic conductivities of amorphous polyviologens with polyethers were influenced only by glass transition temperature changes. New imidazolium ionic liquid monomers and imidazolium based polymers were synthesized for potential applications in electroactive devices, such as actuators. Structure-property relationships for pendant imidazolium polyacrylates and main-chain imidazolium polyesters were investigated. Terminal ethyleneoxy moeties enhanced ionic conduction 2~3 times; however, the alkyl chain length effect was negligible. For the imidazoium polyesters, higher ion conductivities result from 1) mono-imidazolium over bis-imidazolium, and 2) bis(trifluoromethanesulfonyl)imide polymers over hexafluorophosphate analogs. A semi-crystalline hexafluorophosphate polyester with C₁₀-sebacate-C₁₀, displayed 400-fold higher ionic conductivity than the amorphous C₆-sebacate-C₆ analogue, suggesting the formation of a biphasic morphology in the former polyester. New dicationic imidazolium salts have interesting features. 1,2-Bis[N-(N'-alkylimidazoilum)]ethane salts stack well in the solid state and possess multiple solid-solid phase transitions. They complex with dibenzo-24-crown-8 and a dibenzo-24-crown-8 based pyridyl cryptand with <i>K_a</i> = ~30 and 360 M¹, respectively. Some of these dicationic imidazolium salts have low entropies of fusion, typical of plastic crystals. These newly discovered imidazolium homopolymers have ionic conductivities up to 10⁴ (S cm⁻¹); however, better properties are still required. Well-designed block copolymers should provide both good electrical and mechanical properties from bicontinuous morphologies, such ion channels. / Ph. D.

Perfluorosulfonate ionomers, such as Nafion® have been shown to demonstrate a profound affinity for large cationic complexes, and the study of polymer-bound cations may provide insight regarding Nafion® morphology by contrasting molecular size with existing models. The trimetallic complex, [{(bpy)2Ru(dpp)}2RhBr2] 5+, is readily absorbed by ion exchange into Na+ -form Nafion® membranes under ambient conditions. The dimensions of three different isomers of the trimetallic complex are estimated to be: 23.6 Å × 13.3 Å × 10.8 Å, 18.9 Å × 18.0 Å × 13.7 Å, and 23.1 Å × 12.0 Å × 11.4 Å, yielding an average molecular volume of 1.2×103 Å3 . At equilibrium, the partition coefficient for the ion-exchange of the trimetallic complex into Nafion® from a DMF solution is 5.7 × 103 . Furthermore, the total cationic charge of the exchanged trimetallic complexes counterbalances 86 ± 2% of the anionic SO3 − sites in Nafion®. The characteristic dimensions of morphological models for the ionic domains in Nafion® are comparable to the molecular dimensions of the large mixedmetal complexes. Surprisingly, SAXS analysis indicates that the complexes absorb into the ionic domains of Nafion® without significantly changing the ionomer morphology. Given the profound affinity for absorption of these large cationic molecules, a more open-channel model for the morphology of perfluorosulfonate ionomers is more reasonable, in agreement with recent experimental findings. In contrast to smaller monometallic complexes, the time- v dependent uptake of the large trimetallic cations is biexponential. This behavior is attributed to a fast initial ion-exchange process on the surface of the membrane, accompanied by a slower, transport-limited ion-exchange for sites in the interior of the ionomer matrix. The development of Nafion®/[{(bpy)2Ru(dpp)}2RhBr2] 5+ modified electrodes is also described for both FTO electrodes and materials made from electrospun carbon mats. The [{(bpy)2Ru(dpp)}2RhBr2] 5+ complexes behave as photocatalytic hydrogen production catalysts in the Nafion® membrane. Furthermore, a second bulk photoelectrolysis experiment with the Nafion®/[{(bpy)2Ru(dpp)}2RhBr2] 5+/FTO electrodes shows an enhancement of catalytic activity compared to the first photoelectrolysis experiment. This enhancement is attributed to halide loss following the first reduction process. Lastly, electrospun carbon nanofiber mats behave as electron donor materials for [{(bpy)2Ru(dpp)}2RhBr2] 5+/Nafion® membranes. / Ph. D.

The development of organic materials displaying room-temperature phosphorescence is a research field that has attracted more and more attention in the last years. Most studies focus on designing or optimizing emitter molecules to increase the phosphorescent performance in host:emitter systems. Rarely, the overall thin-film preparation routines are compared with respect to their triplet-state luminescence yield. Herein, different film preparation techniques are investigated using the very same emitter molecule. A variation of host polymer, post-annealing temperature, and fabrication procedure is evaluated with respect to the obtained phosphorescent lifetime, photoluminescent quantum yield, and phosphorescence-to-luminescence ratio. This study elaborates the importance of different film preparation techniques and gathers a concise set of data which is helpful to anyone optimizing the phosphorescence of a particular system.

Online marketing communication provides some of the cutting edge tools that can be used by guest houses to communicate their product and service offerings. The purpose of this study was to determine which online marketing communication tools can be used, and are in fact currently used by guest houses in Pretoria East. The results obtained from this study can assist guest house owner/managers in Pretoria East with decision-making on the communication of off-line and online marketing communication tools to be included in their marketing strategy. Primary data was collected by means of a survey with guest house owners/managers in Pretoria East. Specific corpographic details of guest houses in Pretoria East were identified. Furthermore, the most frequently used off-line and online marketing communication tools were identified, as well as the number of guest houses that have websites and the content of these websites. The findings suggest that guest houses in Pretoria East have to invest more time and money in implementing certain online marketing communication tools, such as social networking and use of Search Engine Optimisation (SEO). By implementing online marketing communication tools like these, guest houses in Pretoria East could enhance customers‟ awareness of a guest house. This study verified the importance of electronic tools such as the Internet and Web as an integral part of an organisation‟s marketing strategy, specifically for small businesses in the service sector, such as guest houses. / Business Management / M. Com. (Business Management)

Les sels d’imidazolium ont un rôle important dans certaines protéines et acides nucléiques et ont été utilisés à de nombreuses reprises dans des assemblages supramoléculaires en raison de leurs propriétés uniques. Les sels de diimidazolium dérivés sont toutefois moins connus. Ils ont pour l’instant uniquement été utilisés comme des précurseurs de carbènes N-hétérocycliques. Ils sont donc à la base de plusieurs catalyseurs utilisés pour des réactions de couplage croisés mais leurs propriétés sont toutefois méconnues dans le cadre de la chimie supramoléculaire. Cette classe de composés a nottament attiré notre attention en raison de la facilité de modification de leurs propriétés physico-chimiques par modification de leur structure chimique. L’objectif général des travaux présentés dans cette thèse est l’étude des propriétés supramoléculaires des sels de diimidazolium disubstitués en solution (aqueuse ou organique), ainsi qu’en phase solide ou cristal-liquide. L’influence de l’espaceur entre les deux noyaux imidazolium ainsi que l’influence des substituants latéraux et des contre-ions a été étudiée. Dans un premier temps, les propriétés de complexation des sels de diimidazolium à des macrocycles sont étudiées. Les sels bromure sont étudiés en solution aqueuse avec plusieurs cyclodextrines et le cucurbit[7]uril, et les sels hexafluorophosphate sont étudiés en solution organique pour leur complexation avec l’éther couronne DB24C8 et un calix[4]arène. Cette nouvelle classe de composés a montré de très bonnes propriétés de complexation à ces différents macrocycles en solution et a également permis de contrôler différents assemblages supramoléculaires à l’interface air-eau. Dans un deuxième temps, l’étude des sels de phénylènediimidazolium a permis de modifier les propriétés de complexation en solution pour obtenir la formation de complexes multiples avec le cucurbit[7]util en solution aqueuse. Cette même famille de composés a également permis la formation de cristaux liquides ioniques lorsque les substituants sont des chaînes alkyles plus longues. La résolution de plusieurs structures cristallines de différents sels de diimidazolium a finalement permis de comprendre la nature des interactions intermoléculaires à l’état cristallin. La recherche présentée dans cette thèse a donc permis une étude détaillée des propriétés supramoléculaires des sels de diimidazolium dans tous les états de la matière qui leur sont accessibles. / Imidazolium salts play an important role in different proteins and nucleic acids and have been used many times in supramolecular assemblies due to their unique properties. Diimidazolium salts derived from imidazolium salts are less known. To date, they have only been used as precursors for N-heterocyclic carbenes, which are used to catalyze various cross-coupling reactions. Their properties are not well known in supramolecular chemistry. This class of compounds attracted our attention because of the ease of tuning their properties by modifying their chemical structure. The main goal of the research presented in this thesis was to study the supramolecular properties of disubstituted diimidazolium salts in solution (aqueous or organic solution), in the solid state and in the liquid-crystalline state. The role of the spacer between the two imidazolium moieties, of the sidechains and of the counterions was studied. Firstly, the complexation between diimidazolium salts and various macrocycles was studied. Bromide salts were studied in aqueous solution with cyclodextrins and cucurbit[7]uril, while hexafluorophosphate salts were studied in organic solution with a DB24C8 crown ether and a calix[4]arene. This novel class of compounds showed very promising complexation properties with these macrocycles in solution and also allowed us to control the formation of various supramolecular assemblies at the air-water interface. Secondly, phenylenediimidazolium salts were studied and allowed the modification of the complexation properties in aqueous solution. Multiple complexes can be formed simultaneously with cucurbit[7]uril in aqueous solution. The same class of compounds also has the ability to yield ionic liquid crystals when the alkyl sidechains are long. The resolution of the crystalline structures of some synthesized diimidazolium salts allowed us to understand the nature of the intermolecular interactions in the solid state. The research presented in this thesis is a complete study of the supramolecular properties of diimidazolium salts in every accessible state of matter.