<p>Information about protein structures is important in many areas of life sciences, including structure-based drug design. Gas phase methods, like electrospray ionization and mass spectrometry are powerful tools for the analysis of molecular interactions and conformational changes which complement existing solution phase methods. Novel techniques such as single particle imaging with X-ray free electron lasers are emerging as well. A requirement for using gas phase methods is that we understand what happens to proteins when injected into vacuum, and what is the relationship between the vacuum structure and the solution structure.</p><p>Molecular dynamics simulations in combination with experiments show that protein structures in the gas phase can be similar to solution structures, and that hydrogen bonding networks and secondary structure elements can be retained. Structural changes near the surface of the protein happen quickly (ns-µs) during transition from solution into vacuum. The native solution structure results in a reasonably well defined gas phase structure, which has high structural similarity to the solution structure. </p><p>Native charge locations are in some cases also preserved, and structural changes, due to point mutations in solution, can also be observed in vacuo. Proteins do not refold in vacuo: when a denatured protein is injected into vacuum, the resulting gas phase structure is different from the native structure.</p><p>Native structures can be protected in the gas phase by adjusting electrospray conditions to avoid complete evaporation of water. A water layer with a thickness of less than two water molecules seems enough to preserve native conditions.</p><p>The results presented in this thesis give confidence in the continued use of gas phase methods for analysis of charge locations, conformational changes and non-covalent interactions, and provide a means to relate gas phase structures and solution structures.</p>

In this Thesis, two problems were studied: a direct vacuum acceleration of electrons by a tightly focused ultrashort relativistic laser pulse and ion acceleration in the process of spherical laser-heated plasma explosion. The electromagnetic field of a tightly focused laser pulse was evaluated numerically by means of Stratton-Chu integrals. The properties of the focused field were analyzed in detail for a plane wave or a macroscopically large Gaussian beam incident onto the mirror. Free electrons moving in the tightly focused field were found to accelerate by two possible mechanisms: focal spot acceleration and capture-and-acceleration scenario. The two mechanisms were studied in detail. Comparison of the mirror-focused field with first- and fifth-order paraxial fields is performed. A 3D electromagnetic PIC code SCPIC was created for simulations of pulse interaction with targets having a finite number of particles interacting with each other by collective fields. Atto-second bunch formation was observed in the interaction with ultra-small or ultra-thin targets. Physical mechanism of bunch formation is explained. The problem of electrostatic explosion of a nano-scale spherical plasma with initially hot electrons and cold ions was solved numerically. Expansion in a wide regime of electron temperature $0 < T leq infty$ was studied in detail for different initial density profiles of plasma. Favorable conditions for obtaining mono-energetic ions resulting from the explosion were specified in single and two ionic species cases. In case of a two-species explosion, the number of mono-energetic, $deltavarepsilon/varepsilon < 10\%$, ions can be as high as 70-80\% of the total light ions for a wide range of electron temperatures.

Phase behaviour information is essential for the development and optimization of hydrocarbon resource production, transport and refining technologies. Experimental data sets for mixtures containing heavy oil and bitumen are sparse as phase behaviour data are difficult to obtain and cost remains prohibitive for most applications. A computational tool that predicts phase behaviours reliably for mixtures containing such ill-defined components, over broad temperature, pressure and composition ranges would play a central role in the advancement of bitumen production and refining process knowledge and would have favourable impacts on the economics and environmental effects linked to the exploitation of such ill-defined hydrocarbon resources. Prior to this work, predictive computational methods were reliable for dilute mixtures of ill-defined constituents. To include a much wider range of conditions, three major challenges were addressed. The challenges include: creation of a robust and accurate numerical approach, implementation of a reliable thermodynamic model, and speciation of ill-defined constituents like Athabasca Bitumen Vacuum Residue (AVR). The first challenge was addressed by creating a novel computational approach based on a global minimization method for phase equilibrium calculations. The second challenge was tackled by proposing a thermodynamic model that combines the Peng-Robinson equation of state with group contribution and related parameter prediction methods. The speciation challenge was addressed by another research group at the University of Alberta. Pseudo components they proposed were used to assign groups and estimate thermodynamic properties. The new phase equilibrium computational tool was validated by comparing simulated phase diagrams with experimental data for mixtures containing AVR and n-alkanes. There is good qualitative and quantitative agreement between computed and experimental phase diagrams over industrially relevant ranges of compositions, pressures and temperatures. Mismatch was only observed over a limited range of compositions, temperatures and pressures. This computational breakthrough provides, for the first time, a platform for reliable phase behaviour computations with broad potential for application in the hydrocarbon resource sector. The specific computational results can be applied directly to solvent assisted recovery, paraffinic deasphalting, and distillation and refining processes for Athabasca bitumen a strategic resource for Canada. / Chemical Engineering

The curiosity of researchers to find novel characteristics and properties of matter constantly pushes for the development of instrumentation based on X-radiation. I present in this thesis techniques for electron spectroscopy based on developments of X-ray sources both in time structure and energy. One part describes a laser driven High-Harmonic Generation source and the application of an off-plane grating monochromator with additional beamlines and spectrometers. In initial experiments, the source is capable of producing harmonics between the 13th and 23rd of the fundamental laser 800 nm wavelength. The intensity in the 19th harmonic, after monochromatization, was measured to be above 1.2·1010 photons/second with a repetition rate of 5 kHz.  The development of a chopper system synchronized to the bunch clock of an electron storage ring is also presented. The system can be used to adjust the repetition rate of a synchrotron radiation beam to values between 10 and 120 kHz, or for the modulation of continuous sources. The application of the system to both time of flight spectroscopy and laser pump X-ray probe spectroscopy is shown. It was possible to measure triple ionization of Kr and in applied studies the valence band of a laser excited dye-sensitized solar cell interface. The combination of the latter technique with transient absorption measurements is proposed. The organic molecule maleic anhydride (MA) and its binding configuration to the three anatase TiO2 crystals (101), (100), (001) has been investigated by means of Xray Photoelectron Spectroscopy (XPS) and Near Edge X-ray Absorption Fine structure Spectroscopy (NEXAFS). The results provide information on the binding configuration to the 101 crystal. High Kinetic Energy Photoelectron Spectroscopy was used to investigate multilayers of complexes of iron, ruthenium and osmium. The benefit of hard X-rays for ex-situ prepared samples is demonstrated together with the application of resonant valence band measurements to these molecules.

During operation of heavy ion accelerators a significant pressure rise has been observed when the intensity of the high energy beam was increased. The cause for this pressure rise is ion induced desorption, which is the result when beam ions collide with residual gas molecules in the accelerator, whereby they undergo charge exchange. Since the change in charge state will affect the bending radius of the particles after they have passed a bending magnet, they will not follow the required trajectory but instead collide with the vacuum chamber wall and gas are released. For the Future GSI project FAIR (Facility for Antiproton and Ion Research) there is a need to upgrade the SIS18 synchrotron in order to meet the requirements of the increased intensity. The aim of this work was to measure the desorption yields, η, (released molecules per incident ion) from materials commonly used in accelerators: 316LN stainless steel, Cu, Etched Cu, gold coated Cu, Ta and TiZrV coated stainless steel with argon and uranium beams at the energies 5-100 MeV/u. The measurements were performed at GSI and at The Svedberg Laboratory where a new dedicated teststand was built. It was found that the desorption yield scales with the electronic energy loss to the second power, decreasing for increasing impact energy above the Bragg Maximum. A feasibility study on the possibility to use laser refractometry to improve the accuracy of a specific throughput system was performed. The result was an improvement by up to 3 orders of magnitude, depending on pressure range.

Two industrial studies and one set of lab scale trials have been done. In addition, a theoretical study has been done. The main focus has been on non metallic inclusion composition during the ladle refining operation in industrial steel production. Sampling has been done together with careful inclusion determination. The inclusion composition is related to different variables. In the industrial trials samples have been taken at different steps during the ladle refining period. Steel and slag composition as well as temperature and oxygen activity have been determined. The thesis is based on five supplements with different major objectives, all related to the inclusion composition. The equilibrium top slag-steel bulk and inclusions-steel bulk were investigated by comparison between calculated and measured oxygen activity values. The oxygen activity and relation to temperature has also been discussed as well as oxygen activity and temperature gradients. The effect of vacuum pressure on inclusion composition has been evaluated in a theoretical study as well as lab scale trials. The inclusion composition has been studied during the industrial ladle treatment process. The inclusion composition was related to top slag composition and other parameters during ladle treatment. The major findings in the thesis are the lack of equilibrium conditions with respect to top-slag and steel bulk before vacuum treatment. The inclusions have been found to be closer to equilibrium with the steel bulk. Al/Al2O3 equilibrium has been found to control the oxygen activity after Al-deoxidation. Evaluation of inclusion composition during the ladle refining has revealed that the majority of the inclusions showed a continuous composition change throughout the ladle refining process, from high Al2O3, via MgO-spinel to finally complex types rich in CaO and Al2O3. The final inclusion composition after vacuum treatment was found to be close to the top slag composition. Vacuum pressure has been found to have a theoretical effect on inclusion composition at very low pressures. / QC 20100712

The present thesis was to study non-metallic inclusions during vacuum degassing in ladle treatment. Emphasize was mostly given to liquid CaO-Al2O3 inclusions. A series of industrial experiments were carried out at Uddeholm Tooling AB, Hagfors, Sweden. To gain an insight into the industrial findings, laboratory investigations were also performed. Large number of steel samples were collected and examined. Liquid calcium aluminate inclusions with low SiO2 and high SiO2 were often found with spinel inclusions before vacuum degassing. Laboratory experiments showed that spinel would react with the dissolved Ca in the liquid steel forming calcium aluminate inclusions. This laboratory results agreed with the industrial observation that spinel phase was quite often found in the center of the calcium aluminate phase. After vacuum degassing, most of the inclusions were calcium aluminate liquid inclusions. When dissolved Al level was low, 2 types of liquid calcium aluminate inclusions with considerably different SiO2 contents were found to coexist even at the end of the process. In view of the lack of the thermodynamic data for SiO2 activities in the low silica region, thermodynamic measurements were conducted in the CaO-Al2O3-SiO2-MgO system. The experimental results could reasonably explain the coexistence of the two types of the liquid oxide inclusions. While the total number of inclusions decreased during vacuum degassing, the number of bigger inclusions (&gt;11.3 μm) increased generally in used ladles. This finding was in accordance with the previous studies, wherein, ladle glaze was found to be responsible for the supply of bigger inclusions. The behaviors of several types of inclusions in liquid steel were examined using a laser scanning confocal microscope (LSCM). While alumina inclusions tended to impact on each other, agglomerate and grow very quickly, none of the other types of inclusions, such as spinel and calcium aluminate was observed to agglomerate. The results of LSCM study agreed well with the industrial observation. Examination on a huge number of inclusions did not show any indication of impact and physical growth of the inclusions, except the alumina inclusions. The removal of inclusions around open-eye in a gas-stirred ladle was experimentally studied by a cold model with oil and water. Most of the simulated inclusions were brought up to the oil phase by gas-water plume. Inclusion removal into oil layer took place when the inclusions passed through the sphere-bed of the oil layer around the open-eye. A calculation showed that the contribution of metal-gas plume in inclusion removal was much larger than that of buoyancy mechanism. The results of the industrial experiments revealed that the inclusions distribution strongly depended on stirring condition. When a ladle was stirred by both gas and induction, inclusion removal near slag layer was significant. / QC 20100803

This thesis treats the development of packaging and integration methods for the cost-efficient encapsulation and packaging of microelectromechanical (MEMS) devices. The packaging of MEMS devices is often more costly than the device itself, partly because the packaging can be crucial for the performance of the device. For devices which contain liquids or needs to be enclosed in a vacuum, the packaging can account for up to 80% of the total cost of the device. The first part of this thesis presents the integration scheme for an optical dye thin film NO2-gas sensor, designed using cost-efficient implementations of wafer-scale methods. This work includes design and fabrication of photonic subcomponents in addition to the main effort of integration and packaging of the dye-film. A specific proof of concept target was for NO2 monitoring in a car tunnel. The second part of this thesis deals with the wafer-scale packaging methods developed for the sensing device. The developed packaging method, based on low-temperature plastic deformation of gold sealing structures, is further demonstrated as a generic method for other hermetic liquid and vacuum packaging applications. In the developed packaging methods, the mechanically squeezed gold sealing material is both electroplated microstruc- tures and wire bonded stud bumps. The electroplated rings act like a more hermetic version of rubber sealing rings while compressed in conjunction with a cavity forming wafer bonding process. The stud bump sealing processes is on the other hand applied on completed cavities with narrow access ports, to seal either a vacuum or liquid inside the cavities at room temperature. Additionally, the resulting hermeticity of primarily the vacuum sealing methods is thoroughly investigated. Two of the sealing methods presented require permanent mechanical fixation in order to complete the packaging process. Two solutions to this problem are presented in this thesis. First, a more traditional wafer bonding method using tin-soldering is demonstrated. Second, a novel full-wafer epoxy underfill-process using a microfluidic distribution network is demonstrated using a room temperature process. / <p>QC 20130325</p>

As the environmental concern grows, researchers try to find material which can be environmental friendly and biodegradable to some extent. At present, flax fibre cannot fully replace glass fibre. Some attempts have been made to replace the glass fibre.<p> Studies show the physical and mechanical properties of natural fibres are comparable with glass fibre, so it can replace glass fibre in the process of making biocomposites. <p> The properties of biocomposites depend on the fibre used. Research shows that to get a better biocomposite, the fibre has to be chemically treated to improve adhesion between fibre and polymer matrix. After the chemical treatment, the fibre has to be dried to minimum moisture content so the drying of flax fibre is essential in the process of making biocomposites. <p> In this research, oilseed flax fibre is dried and drying characteristics were investigated. After drying, the physical properties of the fibre were tested and analysed.<p> The fibre was dried using three different drying methods, namely, microwave, microwave-convection, and microwave-vacuum environments. Curve fitting with four empirical methods has been carried out to determine the drying constant, coefficient of determination and standard error values. The results showed that microwave-vacuum drying method is more efficient (in terms of final moisture content) than microwave and microwave-convection drying. Although microwave-vacuum drying took the most time and did not result in promising colour values, the maximum moisture removal is achieved because fibres can be dried for a longer period of time with a comparatively low temperature.<p> The results of physical properties were analysed for untreated and treated and dried flax fibre. The tensile strength and elastic modulus of untreated and treated fibre did not show any significant change. Because the diameter of flax fibre cannot be consistent, a range of values can be obtained. The diameter range of fibre bundle 30-300 µm was examined for these tests. The tensile strength obtained from these fibre bundles ranged between 16 to 667 MPa and elastic modulus values were 2 GPa up to 63 GPa.<p> The scanning electron micrograph (SEM) was also analysed for untreated and treated-dried fibre. The fibre which was dried with high power or longer period of time showed black spots, probably due to local heating. The fibre dried with microwave-vacuum developed some black spots which were clearly seen in the SEM.<p> Differential scanning calorimetric data showed a shift in temperature of degradation. In this research, degradation temperature of cellulose was found 350(+/-10)°C for the treated and dried flax fibre.<p> In conclusion, the flax fibre has a potential to be used in biocomposite production. The microwave-vacuum works best for drying where the fibre can be dried up to a less than 1% of moisture content.

Im Rahmen der Arbeit wurde das Potential von Magnesium für den Einsatz im Fahrwerk eines Automobils, am Beispiel der Querbrücke des Hinterachsträgers, ermittelt. Verschiedene Mg-Legierungen wurden im konventionellen und vakuumunterstützen Druckguss vergossen und der Al-Legierung vergleichend gegenübergestellt. Es wurden in einem ersten Schritt statische und zyklische Werkstoffkennwerte sowie Materialmodelle erforscht und bewertet. Verschiedene Lastfälle im Standard- und Sonderfahrbetrieb wurden durch statische und zyklische Betriebsfestigkeitssimulationen abgesichert. Konstruktive Bauteiloptimierungen waren notwendig um den Werkstoff Magnesium an die Anforderungen der Querbrücke anzupassen. Äußere Umwelteinflüsse im Fahrbetrieb machten ein Korrosionsschutzkonzept für die Querbrücke aus Magnesium notwendig. Untersucht wurden dabei verschiedene Maßnahmen zur Vermeidung von Kontakt- und Oberflächenkorrosion. Grundsätzlich scheint der Einsatz von Magnesium im Fahrwerk im Bereich mittlerer Betriebsbelastungen denkbar.