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Bij het uitwerken van dit onderzoeksproject willen wij nagaan of de onderwijsbenadering 'blended learning' wel degelijk een meerwaarde biedt voor de motivatie bij leerlingen uit de tweede graad van het secundair onderwijs. Om hierop te kunnen antwoorden, zijn we met behulp van een enquête, uitgewerkt door Sierens en Vansteenkiste (Sierens & Vansteenkiste, 2009) op basis van de zelfdeterminatietheorie van Deci en Ryan (Deci & Ryan, 2002) aan de slag gegaan. We hebben in vier verschillende klassen twee keer een enquête afgenomen. Op deze manier kregen we een goed beeld van de evolutie in motivatie bij de leerlingen. Het uiteindelijke onderzoek en de resultaten kan u terugvinden in deze paper.

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Selective thin films of HKUST-1 and ZIF-8, as well as a new IRMOF-3 derivative, were developed for the adsorption of NH_3 and H_2S in intelligent packaging. Intelligent packaging is a means to reduce the food waste problem by incorporating a sensor in the package material providing extra information about the package contents. One important aspect is the detection of released compounds during the deterioration of food. The sensor needs a coating able to selectively adsorb these compounds to increase the sensor sensitivity. In this work, interest is taken in the adsorption of NH_3 and H_2S by using the metal-organic frameworks HKUST-1, IRMOF-3 and ZIF-8. Specific synthesis methods are needed to create adequate thin films of these crystalline materials. Silicon wafers and mesoporous silica coated on silicon wafers serve as substrates for metal-organic framework coatings. In addition, the adsorption characteristics of these coatings needed to be tested. The change in refractive index was probed during adsorption by using the in-situ ellipsometry technique. The HKUST-1 on mesoporous silica synthesis procedure by manual dip coating resulted in weakly crystalline coatings. On the other hand, HKUST-1 on silicon wafers coated by an in-situ crystallization technique at room temperature yielded an oriented crystal structure in one direction. The automated dip coating technique used to develop IRMOF-3 coatings on mesoporous silica failed to create a crystalline IRMOF-3 coating. During the IRMOF-3 synthesis, a new type of functional material was created. Most likely, an amorphous IRMOF-3 structure had formed. ZIF-8 coated on mesoporous silica by the in-situ crystallization technique at room temperature resulted in a weakly crystalline coating. The same method with the usage of silicon wafer substrates yielded adequate double layered crystalline coatings when the silicon wafers were pre-cleaned. Without pre-cleaning and repeating the synthesis method three times, one layered homogeneous continuous coatings were obtained with strong crystal orientation. The effect of pre-cleaning could be coincidental. Ammonia sensitivity corresponding to the refractive index increase of the coatings during a fifteen minute batch phase of 50ppm NH_3 was determined by ellipsometry. This yielded for HKUST-1 on mesoporous silica 0.0021 and for HKUST-1 on a silicon wafer 0.0229. The refractive index change of the IRMOF-3 derivative was 0.0055. When a modified mesoporous silica coating acted as a substrate during IRMOF-3 synthesis, a refractive index increase of 0.0127 was realized. NH_3 Adsorption on saturated HKUST-1 and IRMOF-3 coatings with water yielded a refractive index increase of 0.001 and 0.01, respectively. In absolute values, the HKUST-1 performed better in comparison to the IRMOF-3 derivative. However, when the results were normalized, taking material characteristics into account, the performance was almost the same. Exposure of a HKUST-1 thin film to 2000-2500ppm H_2S resulted in a refractive index rise of 0.3 as well as a complete destruction of the HKUST-1 framework. ZIF-8 coatings also got completely destroyed during 2000-2500ppm H_2S exposure, whereas almost no detection could be observed during adsorption of CO_2, NH_3 or ethanol.

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This master’s thesis studies the loyalty of political advisers in the cabinets of the European Commission. The loyalty of European commissioner cabinet members is addressed through a typology consisting of two dimensions. The first dimension is based on an existing typology, that was first proposed by Thuillier (1999) to classify cabinet members of the French ministerial cabinets. This dimension investigates the mobility of cabinet members. The second dimension is added to clarify the influence of Member States in the Commission cabinets and looks at the professional networks of cabinet members. The objective is twofold. First, the research investigates whether or not the loyalty of European commissioner cabinet members can be discussed using the proposed typology, of which a big part originates from a typology created for the national level. As a second objective, the research aims to put forward some arguments on how the advisers in the European Commission cabinets would be categorized in the typology. The data for the research is collected through ten semi-structured interviews with members of cabinet of the Juncker Commission from March to May 2017. The analysis of this data found that, regarding the professional network dimension, there are differences in the networks that cabinet members have before their appointment. Some are closer tied with the Member States than others. This finding does, however, not mean that these people represent the interests of the Member States. Cabinet members appear to use a professional attitude in their contacts with ‘the country they know best’ and not favour the interests of these countries. Regarding the second dimension of the typology, the research found that in the Commission cabinets examples can be found of all three categories of this dimension. The majority, however, appears to be opportunistic in their mobility. Because of the practice of ‘parachutage’ in the Commission, this type of behaviour is even more apparent for Commission officials in the cabinets than for cabinet members coming from outside the Commission. The different findings of the analysis led to three main conclusions. Firstly, it appears that the influence of Member States in the composition of the cabinets is minimal. Secondly, and related to the first conclusion, the analysis suggests improving the typology by dropping the professional network dimension and expanding the second one with a fourth category, ‘opportunistic within the Commission’. The third and last main conclusion is that in this improved typology, the newly added category ‘opportunistic within the Commission’, would probably contain the biggest share of European commissioner cabinet members. This is the direct result of the big share of Commission officials in the cabinets and the effect of the practice of parachutage in the Commission through the cabinets.

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Water is an essential good that fulfills multiple roles in society. Water is used for drinking, agricultural irrigation, and it acts as a solvent, reactant, or cooling medium in industrial processes. Enormous amounts of fresh water are needed to maintain our standard of living. Water itself is plentiful, but most water on Earth is either saline, found deep underground, or is present as snow, ice, or water vapor and therefore unavailable for immediate use. A dynamic and uneven water distribution combined with high fresh water demand is a recipe for water scarcity. Reports show that one billion people already live in water-stressed areas; this number is likely to increase due to a growing world population, deterioration in water quality, declining groundwater levels, and the intensification of the water-energy nexus. Providing people with water at any time and any place presents the ultimate solution to water scarcity. Taking advantage of the currently untapped but ubiquitous water vapor from atmospheric air paves the way for solving local water scarcity.Water-from-air extraction processes for fresh water production are currently not considered in the water sector, although the technology has been around for some time. This observation necessitates a thorough evaluation of the bottlenecks hindering atmospheric water vapor from becoming a viable fresh water source. Water-from-air technologies are classified and sorted according to their underlying working principles to gain a thorough understanding of the water-from-air field in its current state. Conventional categories of water-from air technologies include direct air cooling and desiccant-based water harvesting. In the air cooling approach, the air cools down below the dew-point to allow for water condensation. Operating in subzero dew-point temperatures should be avoided and call for a different strategy: desiccant-based water harvesting. In this approach, water vapor is captured by a desiccant material. The water evaporates from this material in the next step by thermal heating, facilitating the final condensation step by raising the dew-point. Presented concepts are carried out in a passive operation mode in which the process is carried out based on natural phenomena or an active mode in which an auxiliary energy input is required to carry out the process. The underlying principles, advantages and disadvantages, a thermodynamic analysis, and the achieved efficiencies of devices are presented in this work. The climate-dependent specific water yield (L/kWh), an energy intensity measure, is introduced to evaluate the impact on the water-energy nexus. The low intrinsic specific water yields of water-from-air technologies create a major bottleneck for large-scale implementation. Water consumption in thermoelectric power plants drastically reduces the overall process efficiency in the scope of the water-energy nexus. In addition, current water-from-air extraction devices reach the thermodynamic boundaries, limiting further improvements. Alternative low energy-intensive atmospheric water harvesting concepts are needed to turn water vapor into a viable water resource.Conventional water-from-air harvesting processes are characterized by low maximal specific water yields. The phase transitions of desorption and condensation are energy-intensive process steps. Two alternative concepts are proposed which avoid these transitions and drastically reduce the energy demand. Thermo-responsive polymers are capable of immediately releasing trapped water as a liquid upon heating due to a hydrophilic-hydrophobic configuration change of the polymer chains. Another alternative is deliquescent salt reverse osmosis: the transfer of the seawater desalination concept to land. Deliquescent salts become liquid solutions above a certain relative humidity, making it possible to separate the solution into fresh water and a concentrated brine in a pressure-driven reverse osmosis unit. The concentrated brine can be reused to capture water vapor and close the process cycle. The process fundamentals, technological restrictions, and an energy analysis of these alternative concepts are provided. A world map indicating the optimal water-from-air extraction process is constructed based on regional climate conditions, maximum specific water yields, and practical considerations. The selection of water technologies used to evaluate the water-energy nexus has been updated with the air-based fresh water production technologies covered in this work.Most water-from-air extraction processes operate in two consecutive steps: water vapor capturing with a desiccant followed by a water separation step. The rate of water uptake is crucial for maximizing water production, but research focuses mainly on water uptake capacity and the separation step. A complete non-isothermal kinetic model of a desiccant bed of particles has been developed to elucidate the prevailing kinetic bottlenecks during water vapor adsorption. The mass transfer effects of particle diffusion and bed diffusion are investigated in conjunction with the heat transfer phenomena of bed thermal conductivity and air convection. The validity of the commonly held assumptions of neglecting thermal radiation and convective water vapor supply has been checked. In addition, the use of a complete multiphysics model allows for large step sizes of the boundary conditions, making it possible to determine the effect of the nonlinear adsorption isotherm shape on the mentioned mass and heat transfer phenomena. In general, limited improvements in water uptake rate are expected by enhancing heat and mass transfer. Practical solutions are given to improve the slow water vapor uptake of the passive desiccant-based technology.

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Microfinancieringsinstellingen (MFI’s) hebben als doel klanten uit de armoede te helpen en trachten bijgevolg een sociale missie te volbrengen. Door de uitbreiding van het aantal MFI’s, is het volbrengen van deze missie echter vaak een nevendoel geworden. Uit commerciële overwegingen gaan deze MFI’s namelijk meer de nadruk leggen op het behalen van de financiële objectieven. De sociale ratings en de daarbij horende traditionele determinanten, vormen dan ook het onderwerp van dit rapport. De literatuur geeft namelijk aan dat onderzoekers over weinig betrouwbare determinanten beschikken om sociale ratings te kunnen verklaren. Deze thesis probeert hieraan tegemoet te komen door betrouwbare maatstaven van sociale ratings te identificeren. Het onderzoek toont aan dat de variabelen ‘kredietcliënten’ en ‘gemiddeld leningsbedrag geschaald volgens het BBP per capita’, dezelfde invloed vertonen als deze die onderzoekers hieromtrent aanhouden. De variabelen omtrent de kwetsbare klanten worden aanzien als niet consistente schatters en vertoonden in de meeste gevallen ook niet de invloed die onderzoekers verwachten. Daarnaast levert deze thesis ook het bewijs van een aantal nieuwe variabelen die bijkomende verklaringskracht bieden aan de spreiding in sociale ratings. Zo is het voor toekomstig onderzoek ook aangewezen dat onderzoekers rekening houden met de ‘debt/equity ratio’, de ‘return on assets’, de ‘ratio omtrent operationele kosten met de gemiddelde leningenportefeuille’, de ‘hoeveelheid geld die een MFI op de bankrekening heeft staan’, het feit of ‘de MFI een eigen rechtsstatus heeft’ en de ‘eventuele reserves om verliezen aan te zuiveren’. Deze thesis levert samen met de literatuur tenslotte het bewijs dat wanneer MFI’s opereren onder NGO’s, coöperatieven en banken, dit telkens een positieve invloed vertoont op sociale performantie.