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A reliable characterization of a MEMS microphone is essential for a better understanding of the device physics, for estimating the device performance and for guidance during the research, for better microphones. The work presented in this report focuses on the investigation and comparison of different measurement principles and techniques used to measure the key device parameters resonance frequency and compliance. The first generation MEMS microphones that are developed by NXP are influenced by mechanical vibrations that reduces the device performance. Therefore, new techniques will be implemented to reduce this noise and these techniques are based upon matching the frequencies of two flexible plates in the microphone sensor, we investigate these resonance frequencies in this thesis. This investigation is performed with two different measurement techniques : electrical impedance measurements and laser vibrometer experiments. These measurements are performed in air and vacuum conditions and the influence of ambient pressure, bias voltage and back volume on the resonance frequency is investigated. The vacuum measurements are in good agreement with the finite element simulation results. Additionally the results obtained from different measurements are compared and the difference between the results are analyzed. Finally, recommendations are made for future measurement conditions and setups.

In the research on solar cells, accurate characterization techniques are of great importance. In this work a specific technique is studied that makes use of transmitted and reflected light from a thin layer. The material properties of transparent conductive oxides (TCOs), silicon and nanoparticles are extracted by fitting a mathematical model on these measured spectra. This model consists of sub-models that describe the physical properties of the layer such as the bandgap of the material or the free carrier absorption. A close fit of the model on the measurements then reveals all these parameters. The modelling is done with the aid of a software package called SCOUT. In this software all the sub-models are available as `building blocks' and one can compose the right interface for a certain material. This method of characterization turns out to be a highly accurate way to obtain material properties. The fitting results of the model on the measured spectra are accurate for all studied materials and an error analysis shows that a unique solution is found for all the parameters. The obtained properties are comparable to values found in literature and results obtained with state of the art characterization techniques. The creation of a specific interface in SCOUT for each material has provided the PVMD group with a powerful tool for optical characterization on which further research on material optimization can be based.

In this Bsc-thesis the thin-sections of the Uithuizermeeden-1A well are studied on mineral content and diagenetic changes with a Leica polarisation microscope and digital camera. Photo’s that have been taken are bundled together in a photo book which can be of use as study material. During Middle and Late Permian times the Netherlands became part of a large, complex, east-west trending sedimentary basin, with a large playa lake in the centre. The Variscan mountains in the south provided the siliciclastic sediments and early Permian volcanic deposits were the source of heavy minerals, volcanic rock fragments and mica’s. The Uithuizermeeden-1A well was located at the margin of the playa lake, which was characterized by a wetter and more cemented setting. Because of its deep-burial regimes the UHM-1A sediments have undergone several diagenetic processes, but stabilising, pore blocking cements didn’t allow mechanical compaction. At later time dissolution of these stabilising cements and unstable feldspars and rock fragments provided excellent reservoir conditions. With a Gas-Water-Contact on a depth of 2988 meter, minerals within the gas zone have been excluded of contact with formation waters for 200 million years, which inhibits further chemical diagenetic changes. Illitisation, the process of formation of pore-bridging, pore-filling or meshwork hairy illite, could only be seen within the Water Zone. Petrographic data also showed a reduction of K-feldspars from an average of 4%in the Gas Zone to an average 2% in the Water Zone. So gas charge arrests illitisation and diagenetic changes to unstable minerals.

While hydrodesulfurization (HDS) is a process that has already been used for over 50 years and has received large attention in the literature, the world-wide trend towards ultra clean fuels has renewed the interest in HDS catalysis research. EU regulations with respect to fuel specifications involve reduction of the sulfur content in diesel from 350 ppm today to 50 ppm in 2005. These regulations are set up because of environmental concern, since sulfur in fossil fuels produces SO2 after burning the fuel and SO2 is one of the main causes of acid rain. Therefore, sulfur that is present as a natural organic component in crude oil is removed in the oil refinery in the presence of H2 by a process called hydrodesulfurization. Even more stringent specifications are being discussed in Europe, where Germany is considering a 10-ppm sulfur limit on both gasoline and diesel. Meeting these severe limits in the most cost-effective way represents a significant challenge to the industry. Since HDS at low sulfur levels is very different from conventional HDS (in which CoMo catalysts are commonly applied), one of the solutions is development of new HDS catalysts. NiW catalysts were found to be capable of desulfurizing the most refractory aromatic sulfur compounds and thus suitable for HDS at low sulfur levels.Therefore, NiW catalysts were extensively studied in this Ph.D. project with Mössbauer spectroscopy, extended X-ray absorption fine structure, high-resolution transmission electron microscopy and HDS activity tests. This resulted in a description of structure-activity relationships for NiW catalysts on different support materials. Furthermore, the study of CoW catalysts revealed why these catalysts have an inferior HDS activity. This fundamental knowledge can be used to develop "design rules" for better performing HDS catalysts in the future. The results are described in the thesis entitled "Characterization of NiW and CoW hydrotreating catalysts".

For efficient production of hydrocarbons from subsurface reservoirs it is important to understand the spatial properties of the reservoir. As there is almost always too little information on the reservoir to build a representative model directly, other techniques have been developed for generating reservoir models. Different assumptions about the distribution of, and relationships between these properties are required for each different technique. However, it is poorly understood how these assumptions, and errors thereof, affect the predictive capability of the resulting reservoir models. In this study these relationships are analyzed from several different perspectives.

The Ram Group in Jordan forms part of a massive and voluminous quartz-rich blanket that covered North Africa and Arabia, the former northern margin of Gondwana during the Early Paleozoic. The lack of vegetation on the vast peneplained and tectonically stable margin resulted in the development of extensive alluvial systems markedly different in scale from modern systems. In the Petra area, the Ram Group is conformed by the Salib, Abu Kusheiba and Umm Ishrin formations. Its onset and development are admirably displayed allowing a unique oportunity to perform detailed sedimentological studies. In the paleogeographic context of the Early Paleozoic, the detailed analysis of five lithofacies and interpretation of their three major associations in terms of architectural elements, the study of the mineralogical development throughout the sequence and the ichnofacies content from new ichnofossil discoveries are all gathered in order to reconstruct a depositional and architectural model for the Ram Group. The base of the sequence buries a remarkable 100-metre high paleorelief of the Precambrian basement inherited from volcanic activity. Upward, the sedimentary package describes a 110-metre-thick fining/thinning (salib Formation) and coarsening/thickening (Abu Kusheiba Formation) cycle until drastic development of a >500-metre-thick, massive, medium-grained cross-bedded quartzarenite (Umm Ishrin Formation). The environments of depositions evolved from shallow marine shelf to delta-front and delta braidplain until definite onset of a continent-wide alluvial plain dominated by shallow, perennial, sand-bed braided rivers on the distal margins of Gondwana. Short-lived transgressions and tidal currents reworked parts of abandoned braidplains. The Umm Ishrin Formation is an excellent analogue for subsurface braided hydrocarbon reservoirs. Reservoir characterization from outcrop studies results in a vertical stack of laterally extensive sheet-like units with remarkable high net-to-gross ratios. Radial flow is expected and drainage would be driven under gravity dominated flow due to good hydraulic connectivity in a rather thick and homogeneous sand-rich formation. Reservoir heterogeneities such as small, isolated fine-grained interbeds are randomly distributed through the reservoir. Rather than impeding cross-vertical flow, these barriers may be useful in preventing water or gas coning when correct placing of production wells.

Wintershall is operating a number of Buntsandstein fields in the Southern North Sea. It has proven a major exploration challenge in the area to predict the reservoir quality of these fields based on seismic data only. The effect of salt present in the area plugging the pore space leads at first sight to similar seismic responses on post-stack data as for gas filled reservoirs. This study aims to gain better insight into the (subtle) differences in seismic response induced by water-, gas- or salt-fill scenario. The approach adopted is by studying the seismic response at various existing wells in one of the fields and the corresponding seismic responses of the processed 3D seismic survey. First a thorough analysis of the log responses of 13 wells is made and the effect of a.o. depth trends, compaction, diagenesis and facies changes to the seismic response is qualitatively investigated. Then, a match between the log data and the poststack seismic data is established by creating synthetic seismic data. Finally by using fluid substitution and more recent solid substitution theory, subtle changes in seismic response, both pre-stack and post-stack, between the different porefills are predicted. Based on these modeled predictions recommendations are made concerning the type of data analysis that should be carried out to discern the different porefills on the seismic data. The results of this research should lead to an improved characterization of the Buntsandstein reservoirs and as a consequence, to a higher success rate in drilling (i.e. less “dry wells”).

Abstract not available

Chemical shrinkage and simultaneous build-up of mechanical properties in curing thermosets leads to the build-up of residual stresses and strains. Depending on the constraints these may cause interface failure, dimensional inaccuracy or failure in the thermoset or its surrounding structure. The present work aims at both an improved methodology for the thermo-viscoelastic characterization of curing thermosets and at an improved constitutive model describing their viscoelastic behavior during cure. Firstly: the characterization method. This combination of experiments and dataprocessing gives quite satisfactory predictions of the full relaxation modulus curve at arbitrary conversion and temperature. The method has several advantages relative to classical viscoelastic characterization methods and can also be used for non-curing polymers. Secondly, a new, so-called fully cure dependent relaxation function is developed. A deviatoric constitutive equation, a hereditary integral based on this relaxation function, is implemented in Matlab. The experimental techniques and the constitutive model developed lead to a quite satisfactory representation of the curing induced development of the viscoelastic shear modulus. The expectations to a successful prediction of curing induced stresses are therefore rather positive. However, the current implementation is not yet attractive for finite element purposes; each time step requires a re-evaluation of all former steps. With the characterization method and a more efficient implementation one obtains a powerful tool to study the effectiveness of design choices, like geometry or curing parameters, to avoid curing induced reliability or manufacturing problems.

A new wideband open-loop active harmonic load–pull measurement approach is presented. The proposed method is based on wideband data-acquisition and wideband signal-injection of the incident and device generated power waves at the frequencies of interest. The system provides full, user defined, in-band control of the source and load reflection coefficients presented to the device-under-test at baseband, fundamental and harmonic frequencies. The system capability to completely eliminate electrical delay allows to mimic realistic matching networks using their measured or simulated frequency response. This feature enables active devices to be evaluated for their actual in-circuit behavior, even on wafer. Moreover the proposed setup provides the unique feature of handling realistic wideband communication signals like multicarrier wideband code division multiple access (W-CDMA), making the setup perfectly suited for studying device performance in terms of efficiency, linearity and memory effects. In this work we describe the hardware and signal conditioning of the proposed setup. The high dynamic range, bandwidth and measurement speed of the system, together with its capability to engineer the large-signal operation of an active device, are demonstrated by measuring the improved RF performance of a multicarrier W-CDMA driven laterally diffused metal–oxide–semiconductor device when the electrical delay in the setup is canceled.

Ion exchange resins have found an increasing application in the drinking water treatment sector over the last few decades. The ion exchange resins have a positive ability to remove the charged natural organic matter (NOM). To apply this process in full-scale treatment, the most suitable resin has to be selected and the hydraulic behaviour of the treatment process must be known. This study has the purpose to study the NOM fractions removal with different resins and select the most suitable resin for NOM removal of the Weesperkarspel water. Another purpose is to study the hydraulic behaviours of fluidized ion exchange and testing of the fluidization models of Ergun and Richardson-Zaki. The thesis study is characterizing NOM into the specific fraction and later observing the removal of each fraction with the different ion exchange resins. The kinetic and the equilibrium of NOM removal of each resin are also studied. Four ion exchange resins are tested (Lewatit VP OC 1071, Purolite Macronet 200, Duolite A7 and MIEX DOC). The ultraviolet absorbance method (UV), dissolved organic carbon detection method (DOC), specific ultraviolet absorbance (SUVA), fluorescence excitation emission matrix (fluorescence EEM) and liquid chromatography-organic carbon detector method (LC-OCD) were applied. Weesperkarspel water contains a high degree of aromatic NOM fractions, mostly in the form of humic substances. The Lewatit VP OC 1071 is the most suitable resin for removal of NOM in general view, especially aromatic NOM and humic substances fractions. It appears to be removed as high as 65% and 94% respectively. The MIEX DOC removed 57% aromatic NOM fraction and 70% of humic substances. The pH was found as the dominant parameter for the NOM removal by the weak base Duolite A7. In normal raw water (pH = 7.8), this resin is almost ineffective while it can remove the aromatic NOM up to 35% and humic substances fraction of 45% in raw water pH adjusted to 5. The sorbent Purolite Macronet 200 can remove only biopolymers and neutral NOM fractions. Adsorption is an important mechanism for the removal process of high molecular weight NOM fractions and the neutrals fractions. By using the linear driving force model (LDF) to describe the ion exchange rate of the resin, it was found that MIEX DOC resin can remove NOM faster than other resins. The LDF- k constant of MIEX DOC is also higher than other resins. MIEX DOC has the smallest resin bead size. This can be the reason for the fast removal of NOM. The resin exchange capacity is related with the Freundlich constant K and n . Increase of K and n values lead to increase of exchange capacity. The Lewatit VP OC 1071 has the highest K and n values and thus the highest exchange capacity. The exchange rate and exchange capacity is a specific property of each resin. With help from the LDF model and Freundlich isotherm the breakthrough curve can be determined. The Lewatit VP OC 1071 has longest running time compared with the MIEX DOC and Duolite A7 due to the highest exchange capacity. The hydraulics behaviour of fluidized bed ion exchange has been investigated with the strong base gel resin Lewatit VP OC 1071. The temperature and the feed velocity influence the expanded behaviour. The wet density and wet porosity are important parameters for the model prediction. Combination of mathematical modelling of ion exchange and the treatment conditions of Weesperkarspel drinking water treatment plant, the fluidized ion exchange process can be designed. For Weesperkarspel drinking water treatment plant, the aim is to decrease the DOC concentration of 7.2 mg C/l to 3.0 mg C/l with the fluidized ion exchange process. The 20 fluidized ion exchange reactors with a height of 9 m, 10 m2 of resin bed surface area, a bed height of 2 m and a feed velocity of 20 m/h are designed. The reactors consist of 4 groups, each group is started with delays of 15 days. With this operational step, the running time of each reactor is 60 days. The cost is estimated 11-euro cent per m3 treated water.