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This thesis describes a novel approach to augmenting the combustion performance of hybrid rocket fuels, specifically in terms of regression rate and combustion efficiency. Liquid additives are emulsified into molten paraffin wax using nonionic surfactants and cured to form cylindrical fuel grains. Fuel grains were tested in a lab scale, optically accessible hybrid rocket motor and compared to the performance of neat paraffin fuel grains.

Artros är den vanligaste kroniska ledsjukdomen i Sverige. Symptomen bidrar till nedsatt aktivitetsförmåga i vardagen, ökade sjukskrivningar samt stor vårdkonsumtion. Syftet med denna litteraturstudie var att se om aktivitetsförmågan förändrades hos personer med handartros efter behandling med värme och/eller rörelseträning. Sökningen utfördes i två steg med två sökordssträngar. Databaser som användes var PubMed, Cinahl, Amed, PsycInfo samt Academic Search Elite. Sex kvantitativa originalartiklar som publicerats mellan år 2010-2018 har analyserats och sammanställts i fem kategorier: bedömningsinstrument som mäter den upplevda aktivitetsförmågan, behandlingsmetoder, värmebehandling, rörelseträning och kombination av värme och rörelseträning. Sammantaget föreföll kombinationen värme och rörelseträning öka aktivitetsförmågan hos personer med handartros. Bäst långsiktig effekt uppnåddes då värme och rörelseträning kombinerades. Då det finns få studier gjorda om värme och rörelseträning, vore det värdefullt med ytterligare studier för att få större kunskap om behandlingseffekterna.

<p>There is a need for reliable valves and pumps in microfluidics. A good microactuator is the key for low cost and high performance of these components.</p><p>Paraffin wax is a promising material to be used as actuator material as is can produce large forces and large strokes. Further, the material is inexpensive and, none the less, the thermal heating of the material can be made with low voltages. All these properties are of interest in flow control components in microfluidics, and especially for disposables and in potable systems.</p><p>In this work, paraffin wax has been used in devices and concepts. A valve for high-pressures, a peristaltic pump, a multi-stable actuator, and injector has been shown. A material study was performed on binary mixtures of pure paraffin (n-alkanes), and a concept for loading fluid into a sealed reservoir was shown as well. Several injectors were demonstrated in a Lab-on-a-chip system with other microfluidic components.</p><p>High pressure applications in microfluidics along with the multi-stable actuator show good potential. However, the drive and control has to be further developed.</p>

There is a need for reliable valves and pumps in microfluidics. A good microactuator is the key for low cost and high performance of these components. Paraffin wax is a promising material to be used as actuator material as is can produce large forces and large strokes. Further, the material is inexpensive and, none the less, the thermal heating of the material can be made with low voltages. All these properties are of interest in flow control components in microfluidics, and especially for disposables and in potable systems. In this work, paraffin wax has been used in devices and concepts. A valve for high-pressures, a peristaltic pump, a multi-stable actuator, and injector has been shown. A material study was performed on binary mixtures of pure paraffin (n-alkanes), and a concept for loading fluid into a sealed reservoir was shown as well. Several injectors were demonstrated in a Lab-on-a-chip system with other microfluidic components. High pressure applications in microfluidics along with the multi-stable actuator show good potential. However, the drive and control has to be further developed.

Olefin/Paraffin separation, traditionally carried out by cryogenic distillation, is difficult to achieve due to the similar size and volatility of the components. Recently, many studies have explored membrane separation methods that utilize a metal ion to facilitate preferential olefin transport across the membrane. However, much of this work focuses on smaller molecules, C2-C3, which are gaseous at room temperature, while little work has been done studying separation of larger molecules, C5 and greater, which are generally liquid at room temperature. The processes developed to separate small molecules are not necessarily directly applicable to separate larger molecules. A polymer electrolyte membrane consisting of an active layer of polyethylene oxide (PEO) and silver tetrafluoroborate (AgBF4) has shown high selectivity for separating gaseous olefin/paraffin mixtures. The current project investigates the feasibility of applying this membrane to the separation of pentene and pentane (liquid C5 olefin and paraffin). Process variables investigated are the: pure component permeability ratio, equilibrium sorption uptakes, pure component diffusivities, and stable membrane lifetime. Permeation tests on individual species (n-pentane and 1-pentene) were performed in two operating modes with membranes of varying silver concentrations: direct liquid contact to the membrane, and vapour contact to the membrane. The vapour contact mode showed improved membrane stability in comparison to the liquid contact mode. The olefin/paraffin permeability ratio increases with increasing silver content in the membrane, however, the membrane selectivity is much lower than that achieved with smaller olefin/paraffin pairs. Selective chemical interactions between pentene and the membrane were observed, as the pentene sorption uptake is higher than that of pentane. In addition, a residual fraction is observed – a fraction of the pentene does not desorb from the membrane at ambient conditions – indicating a permanent or semi-permanent interaction. Desorption of pentane is determined to follow a Fickian diffusion model, while desorption of pentene appears to be governed by pseudo-second order kinetics.

Membrane separations provide a potentially attractive technology over conventional processes due to their advantages, such as low capital cost and energy consumption. The goal of this thesis is to design hybrid membranes that facilitate specific gas separations, especially olefin/paraffin separations. This thesis focuses on the designing dendrimer-based hybrid membranes on mesoporous alumina for reverse-selective separations, synthesizing Cu(I)-dendrimer hybrid membrane to facilitate olefin/paraffin separations, particularly ethylene/methane separation, and investigating the influence of solvent, stabilizing ligands on facilitated transport membrane. Reverse-selective gas separations have attracted considerable attention in removing the heavier/larger molecules from gas mixtures. In this study, dendrimer-based chemistry was proved to be an effective method by altering dendrimer structures and generations. G6-PIP, G4-AMP and G3-XDA are capable to fill the alumina mesopores and slight selectivity are observed. Facilitated transport membranes were made to increase the olefin/paraffin selectivity based on their chemical interaction with olefin molecules. Two approaches were explored, the first was to combine facilitator Cu(I) with dendrimer hybrid membrane to increase olefin permeance and olefin/paraffin selectivity simultaneously, and second was to facilitate transport membrane functionality by altering solvents and stabilizing ligands. Promising results were found by these two approaches, which were: 1) olefin/paraffin selectivity slightly increased by introducing facilitator Cu(I), 2) the interaction between Cu(I) and dendrimer functional groups are better known.

In this dissertation, I have investigated applying the laser ablation of microparticle aerosol (LAMA) process to the production of nanocomposite polymer membranes for olefin/paraffin separation. Experimental results for three major thrusts are presented: 1) an investigation into the scalability of the LAMA process, 2) a new laser ablation technique for nanoparticle production from aqueous feedstocks, and 3) characterization of olefin-selective polymer nanocomposite membranes produced using LAMA. The propensity for Ag nanoparticles to form agglomerates in LAMA is investigated. Nanoparticle samples were collected on TEM grids at several feedstock aerosol densities. As the density increased, the particle morphology shifted from single nanoparticles 5 nm in diameter to chained agglomerates of 20 nm diameter primary particles. The results are in agreement with a numerical model of Brownian agglomeration and diffusion. Factors influencing nanoparticle morphology, such as temperature, initial nanoparticle charge, and feedstock aerosol density are discussed. It is shown that agglomeration occurs on a much longer timescale than the other processes, and can be treated independently. A new nanoparticle synthesis technique is presented: laser ablation of aqueous aerosols. A Collison nebulizer is used to generate a mist of ~10 [mu]m diameter water droplets containing dissolved transition metal salts. Water from the droplets quickly evaporates, leaving solid particles which are ablated by an excimer laser. Ablation results in plasma breakdown and photothermal decomposition of the feedstock material. For AgNO₃ ablated in He gas, metallic Ag nanoparticles were produced. For Cu(NO₃)₂ ablated in He gas, crystalline Cu₂O nanoparticles were produced. For Ni(NO₃)₂ ablated in He gas, crystalline NiO nanoparticles were produced. A combination of AgNO₃ and Cu(NO₃)₂ ablated in a reducing atmosphere of 10%H₂/He yielded nonequilibrium Ag-Cu alloy nanoparticles. Membranes composed of poly(ethylene glycol diacrylate) (PEGDA) and Ag nanoparticles were produced by the LAMA process. Permeation and sorption measurements for the light olefins and paraffins were conducted for these membranes. The membranes showed very little improvement in olefin/paraffin selectivity compared with neat PEGDA membranes. Using the LAMA implementation described here, it was impossible to produce membranes with high Ag loading. Whether membranes containing more Ag would exhibit improved selectivity remains an open question. / text

The Laser Ablation of Microparticle Aerosols (LAMA) process produces nanoparticles by ablating microparticles that are entrained in an aerosol. Two of the main advantages of this process are that the particles produced are charged (preventing agglomeration) and bare (without a capping layer). Two different techniques are possible to collect the nanoparticles. In this work, the charged state of the particles formed was utilized to collect them electrostatically. This approach has the additional advantage that particles can be selected according to their size. The focus here was a particular application for gas separation. The nanoparticles produced were directly collected in a polymeric liquid, which was then irradiated with ultraviolet light to form a rubbery film. These membranes were tested for olefin/paraffin gas separation, a challenge that finds many applications, notably in the petroleum industry. / text

Olefin/Paraffin separation, traditionally carried out by cryogenic distillation, is difficult to achieve due to the similar size and volatility of the components. Recently, many studies have explored membrane separation methods that utilize a metal ion to facilitate preferential olefin transport across the membrane. However, much of this work focuses on smaller molecules, C2-C3, which are gaseous at room temperature, while little work has been done studying separation of larger molecules, C5 and greater, which are generally liquid at room temperature. The processes developed to separate small molecules are not necessarily directly applicable to separate larger molecules. A polymer electrolyte membrane consisting of an active layer of polyethylene oxide (PEO) and silver tetrafluoroborate (AgBF4) has shown high selectivity for separating gaseous olefin/paraffin mixtures. The current project investigates the feasibility of applying this membrane to the separation of pentene and pentane (liquid C5 olefin and paraffin). Process variables investigated are the: pure component permeability ratio, equilibrium sorption uptakes, pure component diffusivities, and stable membrane lifetime. Permeation tests on individual species (n-pentane and 1-pentene) were performed in two operating modes with membranes of varying silver concentrations: direct liquid contact to the membrane, and vapour contact to the membrane. The vapour contact mode showed improved membrane stability in comparison to the liquid contact mode. The olefin/paraffin permeability ratio increases with increasing silver content in the membrane, however, the membrane selectivity is much lower than that achieved with smaller olefin/paraffin pairs. Selective chemical interactions between pentene and the membrane were observed, as the pentene sorption uptake is higher than that of pentane. In addition, a residual fraction is observed – a fraction of the pentene does not desorb from the membrane at ambient conditions – indicating a permanent or semi-permanent interaction. Desorption of pentane is determined to follow a Fickian diffusion model, while desorption of pentene appears to be governed by pseudo-second order kinetics.