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In this work, rear-contact passivated Cu(In,Ga)Se2 (CIGS) solar cells were fabricated without any intentional contact openings between the CIGS and Mo layers. The investigated samples were either Na free or one of two Na supply methods was used, i) a NaF precursor on top of the Al2O3 rear passivation layer or ii) an in situ post- deposition treatment with NaF after co-evaporation of the CIGS layer. The thickness of the ALD-Al2O3 passi- vation layer was also varied in order to find an optimal combination of Na supply and passivation layer thickness. Our results from electrical characterization show remarkably different solar cell behavior for different Na supplies. For up to 1nm thick Al2O3 layers an electronically good contact could be confirmed independently of Na deposition method and content. When the Al2O3 thickness exceeded 1 nm, the current was blocked on all samples except on the samples with the NaF precursor. On these samples the current was not blocked up to an Al2O3 layer thickness of about 6 nm, the maximum thickness we could achieve without the CIGS peeling off the Al2O3 layer. Transmission electron microscopy reveals a porous passivation layer for the samples with a NaF precursor. An analysis of the dependence of the open circuit voltage on temperature (JVT) indicates that a thicker NaF precursor layer lowers the height of the hole barrier at the rear contact for the passivated cells. This energy barrier is also lower for the passivated sample, compared to an unpassivated sample, when both samples have been post-deposition treated.

Content Central is a website that allows freelance journalists and photographers to upload their work so that media outlets can buy and publish them. Content Central must moderate the content uploaded to assure that everything is of high quality and that it can be published directly. Right now this is done manually with an editor that work at Content Central. The aim of this thesis is to automate the editorial process on Content Central with the use of natural language processing techniques. The focus of the automation is put on the tasks that consume the most time which is spell checking, formatting and word and sign replacement. The automation of these tasks is done by the development of prototypes. The spell checking task is handled with two prototypes, one prototype uses a dictionary and handles non-word errors and the other prototype uses probability and word trigrams and bigrams to handle real word errors. The formatting and sign replacement is handled by a rule-based prototype. These prototypes are tested on data from Content Central and compared with the results from the editor moderating the same data. Problems are found with the spell checkers, they give many false positives and are therefore deemed not so useful. The formatting and sign replacement prototype achieve a 52.8% recall and 98.6% precision which isestimated to decrease the time the editor spend on content with these errors with at least 51 seconds.

In this thesis Cu(In,Ga)Se2 (CIGS) solar cells with different sodiumdoping of the CIGS absorber and varying Al2O3 rear surface passivationlayer thickness have been manufactured and electrically characterised. Baseline samples and samples without passivation were used asreferences for the passivated samples. For the passivated samplesbetween 1 and 7 nm of Al2O3 were deposited by ALD. The electricalcharacterisation included current-voltage (IV, JV), quantum efficiency (QE, EQE), capacitance-voltage (CV) and temperature dependent currentvoltage (IVT, JVT) measurements. The results show that it is indeed possible to use a tunnel current toconstruct an electrical contact, but that the electrical contact isvery sensitive to sodium doping. The samples with post-depositiontreatment and without Na start to block the tunnel current when thepassivation layer reaches a thickness of about 2 nm, while no blocking of the tunnel current could be observed for the samples with Na pre-deposition. The samples with pre-deposition treatment showed acontinued increase in efficiency all the way to a passivation layerthickness of about 7 nm. When trying to construct samples with eventhicker passivation layer the CIGS started to peel off. For thisreason the optimal thickness for the pre-deposition treated samplescould not be found. The samples with the highest efficiency was thesamples with pre-deposition treatment and thick passivation layer. Those samples showed an increase of 3 percent (absolute) compared tothe unpassivated sample with the same deposition treatment and 1.6 percent higher efficiency compared to the baseline sample. Concluding that tunnelling passivation layer is comparable to the passivationlayer with point contact methods.

In this project the relation between pore size/porosity and the mechanical properties has been studied in the aerogel-like material Quartzene®. Quartzene® is a patented material produced by Svenska Aerogel AB. Density measurements were made on three different types of Svenska Aerogels ABs Quartzene® in the shape of pellets.These three types of Quartzene® is called CMS, ND and E9. The mechanical properties were studied by doing diametrical crush-tests on the pellets. Afterwards the samples were examined through SEM in order to study the structural properties like porosity and microstructure. By examining the materials in this order the group hoped to find a correlation between the mechanical properties and the pore size/porosity. Other microscopic analyses such as TEM and FIB was considered, but due to time limitation these methods were not used. Rough density measurements resulted in an estimated density of 0.82-0.88 g/cm3 for CMS, 0.28-0.30 g/cm3 for E9 and 0.21-0.22 g/cm3 for ND. The crush-tests resulted in a mean fracture stress of 0.81-0.89 MPa for CMS, 0.30 MPa for E9 and 0.20-0.21 MPa for ND. Studying the materials in SEM resulted in an observed mean pore size of 59-73 nm for CMS, 264-362 nm for E9 and 690-710 nm for ND in the mesoporous domain. A subtle relationship between density/pore size and fracture was obtained, with a higher density and smaller pores leading to a higher fracture stress. Due to the lack of data in this study, it is recommended though that this is something that should be examined further before any conclusions can be made. In general Quartzene® has shown to be a brittle material, but this study indicates that the mechanical properties could be controlled in somehow through the microstructure of the material, focusing on controlling the pore sizes. Further investigations in sintering of Quartzene® are also recommended in this study because of its promising effects on the mechanical properties shown in other studies.

Susceptibility to Mycobacterium tuberculosis is characterized by excessive lung inflammation, tissue damage, and failure to control bacterial growth. To increase our understanding of mechanisms that may regulate the host immune response in the lungs, we characterized dendritic cells expressing CD103 (α(E) integrin) (αE-DCs) and CD4(+) Foxp3(+) regulatory T (T(reg)) cells during M. tuberculosis infection. In resistant C57BL/6 and BALB/c mice, the number of lung αE-DCs increased dramatically during M. tuberculosis infection. In contrast, highly susceptible DBA/2 mice failed to recruit αE-DCs even during chronic infection. Even though tumor necrosis factor alpha (TNF-α) is produced by multiple DCs and macrophage subsets and is required for control of bacterial growth, αE-DCs remained TNF-α negative. Instead, αE-DCs contained a high number of transforming growth factor beta-producing cells in infected mice. Further, we show that T(reg) cells in C57BL/6 and DBA/2 mice induce gamma interferon during pulmonary tuberculosis. In contrast to resistant mice, the T(reg) cell population was diminished in the lungs, but not in the draining pulmonary lymph nodes (PLN), of highly susceptible mice during chronic infection. T(reg) cells have been reported to inhibit M. tuberculosis-specific T cell immunity, leading to increased bacterial growth. Still, despite the reduced number of lung T(reg) cells in DBA/2 mice, the bacterial load in the lungs was increased compared to resistant animals. Our results show that αE-DCs and T(reg) cells that may regulate the host immune response are increased in M. tuberculosis-infected lungs of resistant mice but diminished in infected lungs of susceptible mice.