Polyurethane and the analogous ‘polyurethane-urea’ are high performance polymeric materials having remarkable properties such as high stiffness, abrasion and tear strengths. In many studies, the low strength rubbers have been blended with various types of polyurethanes for new and improved materials. However, until now, the reported heterogeneous blends offer only a narrow temperature range of application due to the high temperature softening of their polyurethane (-urea) phase. In addition, the conventional solution-or melt-blending methods are time and energy intensive, which tend to forfeit the economical realization of the reported blends. In contrast to earlier studies, a simplified reactive blending process is suggested to synthesize polyurethane-urea via a prepolymer route during blending with rubbers to obtain novel elastomeric materials having extended performance characteristics. The reactive blending process is opted to prepare blends based on nitrile butadiene rubber (NBR) and in-situ synthesized polyurethane-urea (PUU). The blending is carried out in an internal mixer at a preset temperature of 100°C. The critical temperatures of the reactive blending process are determined from the chemo-rheological analysis of a premix, composed of a 4,4′-diphenylmethane diisocyanate (MDI)/polyether (PTMEG) based prepolymer admixed with 1,3-phenylene diamine (mPD). The prepared NBR/PUU blends exhibit highly improved mechanical properties. Contrary to previous reports, the reinforced dynamic-mechanical responses of the novel blends remain stable till very high temperatures (≥180°C). The influence of diamine type on the in-situ synthesized polyurethane-urea and the performance of prepared blends are investigated. Four different diamines, namely 1,3-Phenylene diamine, 1,4-Bis(aminomethyl)benzene, 4,4′-Methylene-bis(2-chloroaniline) and 4,4ʹ-(1,3-Phenylenediisopropylidene)bisaniline, are selected to chain extend the prepolymer to PUU during blending with NBR. The chemical and domain structure of the PUUs are found to greatly influence the reinforced tensile and dynamic-mechanical responses of the NBR/PUU 70/30 blends. The PUU (based on MDI/PTMEG prepolymer and mPD) is blended with polar (CR, XNBR) and nonpolar (NR, EPDM, sSBR) rubbers. PUU compatibilizes with all the rubbers irrespective of their polarity and reinforces their tensile and dynamic-mechanical characteristics. The use of blends in industrial applications, for example, in a truck tire tread compound and as a roller covering material, is examined. In a simplified tire tread formulation, the carbon black for NR-CB composite is partially replaced with an equivalent quantity of PUU for NR/PUU-CB composite of similar hardness. The dynamic mechanical investigations reveal that the energy dissipation and strain dependent softening is high in NR-CB as compared to the NR/PUU-CB composite. In another application, NBR/PUU blend is successfully tested as a rubber roller covering material. The tested blend-covered roller retains its structural integrity and develops less heat build-up as compared to the silica filled NBR-covered roller. This shows a substantial suitability of the blend-covered rollers for film, printing and textile processing machinery. These novel blends are considered to be the promising new materials for many commercial applications including wheels, rubber rollers, belts or pump impellers.

Solar cells based on organohalide perovskites (PSCs) have made rapid progress in recent years and are a promising emerging technology. An important next evolutionary step for PSCs is their up-scaling to commercially relevant dimensions. The main challenges in scaling PSCs to be compatible with current c-Si cells are related to the limited conductivity of the transparent electrode, and the processing of a uniform and defect-free organohalide perovskite layer over large areas. In this work we present a generic and simple approach to realizing efficient solution-processed, monolithic solar cells based on methylammonium lead iodide (CH₃NH₃PbI₃). Our devices have an aperture area of 25 cm² without relying on an interconnected strip design, therefore reducing the complexity of the fabrication process and enhancing compatibility with the c-Si cell geometry. We utilize simple aluminum grid lines to increase the conductivity of the transparent electrode. These grid lines were exposed to an UV-ozone plasma to grow a thin aluminum oxide layer. This dramatically improves the wetting and film forming of the organohalide perovskite junction on top of the lines, reducing the probability of short circuits between the grid and the top electrode. The best devices employing these modified grids achieved power conversion efficiencies of up to 6.8%.

Polyurethane and the analogous ‘polyurethane-urea’ are high performance polymeric materials having remarkable properties such as high stiffness, abrasion and tear strengths. In many studies, the low strength rubbers have been blended with various types of polyurethanes for new and improved materials. However, until now, the reported heterogeneous blends offer only a narrow temperature range of application due to the high temperature softening of their polyurethane (-urea) phase. In addition, the conventional solution-or melt-blending methods are time and energy intensive, which tend to forfeit the economical realization of the reported blends. In contrast to earlier studies, a simplified reactive blending process is suggested to synthesize polyurethane-urea via a prepolymer route during blending with rubbers to obtain novel elastomeric materials having extended performance characteristics. The reactive blending process is opted to prepare blends based on nitrile butadiene rubber (NBR) and in-situ synthesized polyurethane-urea (PUU). The blending is carried out in an internal mixer at a preset temperature of 100°C. The critical temperatures of the reactive blending process are determined from the chemo-rheological analysis of a premix, composed of a 4,4′-diphenylmethane diisocyanate (MDI)/polyether (PTMEG) based prepolymer admixed with 1,3-phenylene diamine (mPD). The prepared NBR/PUU blends exhibit highly improved mechanical properties. Contrary to previous reports, the reinforced dynamic-mechanical responses of the novel blends remain stable till very high temperatures (≥180°C). The influence of diamine type on the in-situ synthesized polyurethane-urea and the performance of prepared blends are investigated. Four different diamines, namely 1,3-Phenylene diamine, 1,4-Bis(aminomethyl)benzene, 4,4′-Methylene-bis(2-chloroaniline) and 4,4ʹ-(1,3-Phenylenediisopropylidene)bisaniline, are selected to chain extend the prepolymer to PUU during blending with NBR. The chemical and domain structure of the PUUs are found to greatly influence the reinforced tensile and dynamic-mechanical responses of the NBR/PUU 70/30 blends. The PUU (based on MDI/PTMEG prepolymer and mPD) is blended with polar (CR, XNBR) and nonpolar (NR, EPDM, sSBR) rubbers. PUU compatibilizes with all the rubbers irrespective of their polarity and reinforces their tensile and dynamic-mechanical characteristics. The use of blends in industrial applications, for example, in a truck tire tread compound and as a roller covering material, is examined. In a simplified tire tread formulation, the carbon black for NR-CB composite is partially replaced with an equivalent quantity of PUU for NR/PUU-CB composite of similar hardness. The dynamic mechanical investigations reveal that the energy dissipation and strain dependent softening is high in NR-CB as compared to the NR/PUU-CB composite. In another application, NBR/PUU blend is successfully tested as a rubber roller covering material. The tested blend-covered roller retains its structural integrity and develops less heat build-up as compared to the silica filled NBR-covered roller. This shows a substantial suitability of the blend-covered rollers for film, printing and textile processing machinery. These novel blends are considered to be the promising new materials for many commercial applications including wheels, rubber rollers, belts or pump impellers.

Medical imaging based on radioactive tracers exposes the patient to radiation. For this reason, a phantom is preferably used for non-clinical studies such as routine quality assurance and research. The aim of this project was to design, build and test a multi-compartment phantom to be used in dynamic SPECT/CT, PET/CT and PET/MRI studies. By treating each compartment as a biological system and plotting activity distribution, desired characteristics of the phantom can be obtained. A software program was created to simulate compartment activity distribution for different input parameters. Such parameters include number of compartments, administered activity, flow rates between compartments and compartment volume. Based on the simulation, the phantom was designed to meet the desired characteristics. Due to the outbreak of the SARS-CoV-2 virus, no phantom could be built nor tested. Consequently, leading the project to create a foundation that facilitates future building of the phantom. / Medicinsk avbildning med radioaktiva spårämnen utsätter patienter för en stråldos. Av detta skäl används företrädesvis en fantom för icke-kliniska studier såsom rutinmässig kvalitetssäkring och forskning. Syftet med detta projekt var att designa, bygga och testa ett flerkammarfantom som ska användas i dynamiska SPECT/CT, PET/CT och PET/MRI studier. Genom att behandla varje kammare som ett biologiskt system och plotta aktivitetsfördelning kan önskade egenskaper hos fantomen erhållas. Ett program skapades för att simulera aktivitetsdistributionen i flerkammarfantomer för olika in parametrar så som antal kammare, administrerad aktivitet, flöden mellan kammare och kammarvolym. Baserat på simuleringen utformades fantomen för att uppfylla de önskade egenskaperna. På grund av utbrottet av SARS-CoV-2 viruset kunde ingen fantom byggas eller testas. Följaktligen leddes projektet till att skapa en grund som underlättar framtida byggande av fantomen.

This report explains the need to develop a configuration manager that handles transmission equipment which exists in the Swedish Defence telecommunications network. The configuration module will display the configurations and compatibility among the equipment and their software which are all part of the network. Also included in this report are tools, methods and results for the development of a prototype for the configuration manager. The prototype consists fundamentally of a database assisted by a user friendly website. The transmission equipment handles a lot of important transmission of information and is in the hands of a department of SAAB, OFGCA, by orders from the Swedish Defence Materiel Administration (FMV). Within the work included in this order exists a continuous update of both software and hardware which the equipment consists of. Therefore it’s highly important that there is a monitoring of which of the software and hardware is compatible with one another, ensuring that the functions of the system work properly. The consistent updating has resulted in compatibility issues between components and because of this, a need for a configuration manager has arisen. / Den här rapporten uttrycker behovet av att ta fram en konfigurationsmodul för transmissionsutrustningar som ingår i Försvarets telenät (FTN). Konfigurationsmodulen ska mätta ett behov av att kunna se konfigurationerna och kompatibilitet för de utrustningar samt dess programvaror som ingår i telenätet. Rapporten inkluderar även verktyg, metoder och resultat för framtagningen av en prototyp till konfigurationsmodulen. Prototypen består i grunden av en databas med en tillhörande, interaktionsvänlig, hemsida. Transmissionsutrustningarna hanterar en mängd viktig informationsöverföring och en avdelning på Saab, OFGCA, ansvarar för dessa på uppdrag av Försvarets materialverk (FMV). I arbetet som uppdraget innebär pågår en ständig uppdatering av både mjuk- och hårdvara som utrustningarna består av. Det innebär att det är mycket viktigt att det utförs övervakning av vilka mjuk- och hårdvaruversioner som är kompatibla. Detta för att säkerställa att systemets funktioner fungerar korrekt. Den ständiga uppdateringen har medfört kompatibilitetsproblem mellan komponenter och därför har det växt fram ett behov av att ta fram en konfigurationsmodul.