Dissertations / Theses: 'Liquid/liquid separation'

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Simmons, Mark John Harry. "Liquid-liquid flows and separation." Thesis, University of Nottingham, 1998. http://eprints.nottingham.ac.uk/27793/.

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The transport and separation of oil and water is a vital process to the oil and chemical industries. Fluids exiting from oil wells usually consist of gas, oil and water and these three phases need to be transported and separated before they can be processed further. Operation of the primary separators has often proved to be problematic due to the change in composition of the fluids as the well matures, often accompanied by the build up of sand or asphaltenes. These vessels are very expensive to install so there is motivation to improve their design and performance. One major factor affecting separator performance is the phase distribution of the inlet flow, as reflected in the flow pattern and droplet size. In this work, flow pattern boundaries and drop sizes of liquid-liquid dispersions were measured for vertical and horizontal flow of a kerosene and water mixture in a 0.063m tube. Drop size was investigated by using two different laser optical techniques. A laser backscatter technique was employed for concentrated dispersions and a diffraction technique was used at low concentrations. In order to develop a greater understanding of separator performance, a 1/5th-scale model was constructed of diameter 0.6m and length 205m. Residence Time Distributions were obtained for a range of different internal configurations and flow rates using a colorimetric tracer technique. Flow rates of 1.5-4 kg/s oil and 1-4 kg/s water were used and the vessel was equipped with a perforated flow-spreading baffle at the inlet and an overflow weir. Experiments were performed with no internals and with dip or side baffles. The side baffles acted to create quiescent zones within the vessel while the dip baffle caused a local acceleration of both phases. These situations are similar to those that can be caused by blocked internals or existing baffling or structured packing within field separators. A Residence Time Distribution model of a primary separator, the Alternative Path Model, was developed using transfer functions. This model has the ability to reproduce features of the experimental data by representing the flow as a series of continuous stirred tanks in series or in parallel. The model was used to develop parameters that could be used to obtain information about the performance of the separator. This model was also applied to Residence Time Distribution data obtained from field separators by BP Exploration, to relate features of the pilot scale separator to the field vessels.

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Hoettges, Kai F. "Miniaturisation in separation science : liquid-liquid separation on a chip." Thesis, University of Surrey, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252454.

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You, Yuan. "Liquid-liquid phase separation in atmospherically relevant particles." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50466.

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Aerosol particles containing both organic material and inorganic salts are abundant in the atmosphere. These particles may undergo phase transitions when the relative humidity fluctuates between high and low values in the atmosphere. This dissertation focuses on liquid-liquid phase separation in atmospherically relevant mixed organic-inorganic salt particles. Liquid-liquid phase separation has potentially important implications in chemical and physical processes in the atmosphere. A humidity and temperature controlled flow cell coupled to either an optical, fluorescence, or Raman microscope was used to study the occurrence of liquid-liquid phase separation and the phase separation relative humidity (SRH) of particles containing atmospherically relevant organic species mixed with inorganic salts. Organic species in the particles studied include single organic species, such as carboxylic acids, alcohols, and oxidized aromatic compounds, as well as complex laboratory-produced secondary organic material. Material directly collected from the atmospheric environment was also studied. In this dissertation, the effects of oxygen-to-carbon elemental ratio (O:C) of the organic species, salt types, molecular weight of the organic species, and temperature on the occurrence of liquid-liquid phase separation and SRH were studies. The oxygenic-to-carbon elemental ratio was a useful parameter for predicting liquid-liquid phase separation and SRH. Liquid-liquid phase separation did not depend strongly on the molecular weight of the organic species or temperature. The correlation between SRH and O:C in particles containing organic species mixed with different salts were qualitatively similar. Results of this research will help improve the understanding of liquid-liquid phase separation in the atmospheric aerosols, and may, in turn, improve simulations and predictions of atmospheric chemistry and climate. Supplementary materials: http://hdl.handle.net/2429/50970
Science, Faculty of
Chemistry, Department of
Graduate

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Waichigo, Martin M. "Alkylammonium Carboxylates as Mobile Phases for Reversed-Phase Liquid Chromatography." Miami University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=miami1134142423.

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Vliet, Roland Edward van. "Polymer-solvent liquid-liquid phase separation thermodynamics, simulations & applications /." [Amsterdam : Amsterdam : Instituut voor Technische Scheikunde, Universiteit van Amsterdam] ; Universiteit van Amsterdam [Host], 2002. http://dare.uva.nl/document/64948.

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Hemström, Petrus. "Hydrophilic Separation Materials for Liquid Chromatography." Doctoral thesis, Umeå universitet, Kemi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1350.

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The main focus of this thesis is on hydrophilic interaction chromatography (HILIC) and the preparation of stationary phases for HILIC. The mechanism of HILIC is also discussed; a large part of the discussion has been adapted from a review written by me and professor Irgum for the Journal of Separation Science (ref 34). By reevaluating the literature we have revealed that the notion of HILIC as simply partitioning chromatography needed modification. However, our interest in the HILIC mechanism was mainly inspired by the need to understand how to construct the optimal HILIC stationary phase. The ultimate stationary phase for HILIC is still not found. My theory is that a non-charged stationary phase capable of retaining a full hydration layer even at extreme acetonitrile (> 85%) concentrations should give a HILIC stationary phase with a more pure partitioning retention behavior similar to that of a swollen C18 reversed phase. The preparation of a sorbitol methacrylate grafted silica stationary phase is one of our attempts at producing such a stationary phase. The preparation of such a grafted silica has been performed, but with huge difficulty and this work is still far from producing a column of commercial quality and reprodicibility. This thesis also discusses a new method for the initiation of atom transfer radical polymerization from chlorinated silica. This new grafting scheme theoretically results in a silica particle grafted with equally long polymer chains, anchored to the silica carrier by a hydrolytically stable silicon-carbon bond. The hydrolytic stability is especially important for HILIC stationary phases due to the high water concentration at the surface.

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Hemström, Petrus. "Hydrophilic separation materials for liquid chromatography /." Umeå : Department of Chemistry, Umeå University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1350.

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Fang, Yi. "Separation of liquid mixtures by membranes." Thesis, University of Ottawa (Canada), 1997. http://hdl.handle.net/10393/10164.

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The study focused on the interface, morphology and transport involved in pervaporation and reverse osmosis separation of liquid mixtures. The first part of this study concerns pervaporation separation of liquid mixtures. A fluorine-containing surface modifying macromolecule (SMM) was added into a polyethersulfone (PES) membrane casting solution. Because of its lower surface energy, SMM is expected to move up to the top surface of the membrane. The resulting membrane is to have a layer of SMM at the top surface and a PES rich bulk substrate underneath. Asymmetric PES/SMM membranes were fabricated by the phase inversion method under various conditions and tested in pervaporation separation of chloroform/water mixtures. The principal findings are: (i)The contact angles of water on the surface of PES/SMM membranes were significantly larger than those of PES membranes. (ii) The XPS results indicate a much higher fluorine concentration at the membrane surface than in the bulk and upwards orientation of SMM's fluorine tail at the membrane surface. It is concluded that SMM migrates to and accumulates at the membrane-air interface. The membrane surface can be covered by a layer of SMM. (iii) A PES/SMM membrane has a superior performance to a PES membrane for pervaporation separation of chloroform/water mixtures, since the former has a much higher water selectivity than the latter. (iv) A PES/SMM membrane has a higher permeation rate of n-heptane and a lower permeation rate of ethyl alcohol than a PES membrane in pervaporation separation of ethyl alcohol/n-heptane mixtures. The second part of this study concerns reverse osmosis of liquid mixtures. A new method to determine the preferential sorption in binary mixtures based on liquid chromatography is presented. Liquid chromatography and liquid sorption experiments were performed for cellulose acetate butyrate (CAB)/ethyl alcohol/n-heptane system. An interaction force constant characterizing the interaction between the feed species and the membrane was generated and incorporated in the transport equations based on a pore model. Transport simulation was performed for reverse osmosis separation of ethyl alcohol and n-heptane by the CAB membrane. It was found that (i) Both CAB powder and homogenous membrane preferentially sorbed ethyl alcohol from the binary liquid mixtures of ethyl alcohol and n-heptane; (ii) Sorption data can be calculated based on the liquid chromatography data. The good agreement between the two indicates the validity of the proposed approach; (iii) The binary liquid mixtures can be separated by reverse osmosis, and its performance can be calculated using the transport equations based on a pore model. In the last part of this study, reverse osmosis and pervaporation experiments were performed and their results were compared for two cases, namely, separation of ethyl alcohol/n-heptane mixtures by the CAB membrane, and separation of a vinyl acetate/hexane mixture by four different membranes. It was found that pervaporation had a higher separation than reverse osmosis in the separation of ethyl alcohol/n-heptane mixture and vinyl acetate/hexane mixture. (Abstract shortened by UMI.)

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Fine, Bernard Martin. "Light scattering by aqueous protein solutions that exhibit liquid-liquid phase separation." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28079.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Whitaker College of Health Sciences and Technology, 1994.
Includes bibliographical references (leaves 177-184).
by Bernard Martin Fine.
Ph.D.

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Poggemann, Hanna-Friederike. "Investigation on liquid liquid phase separation of lysozyme by dynamic light scattering." Thesis, Stockholms universitet, Fysikum, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-193168.

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The liquid-liquid phase separation (LLPS) of biomolecules is a phenomenon which received a lot of attention in the last years because it is not only related to theformation of membraneless organelles but also to neurodegenerative diseases. Lysozyme is a globular protein that undergoes LLPS in a buffer salt system andfor that it is well investigated with several techniques like microscopy, dynamic lightscattering (DLS) or small-angle X-ray scattering. In this work we investigate the effect of temperature, solvent and sample con-centration on the diffusion coefficient, the hydrodynamic radius and the viscosity oflysozyme using a DLS setup. Furthermore, the influence of these parameters on thecluster formation is addressed. Finally, we investigate the question if the LLPS oflysozyme in a buffer environment effects the formation of dynamic clusters.

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Tizvar, Roza. "Investigation of liquid-liquid extraction process for separation of glycerol and biodiesel." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27490.

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Biodiesel is a sustainable and environmentally friendly source of energy which is now being used as an alternative for fossil fuels worldwide. Glycerol is the main by-product of biodiesel produced via transesterification and must be removed from biodiesel according to the ASTM Standard D-6751-02. This purification has usually been carried out with liquid-liquid extraction with water as a solvent for glycerol. In commonly-used alkali-catalyzed transesterification of waste cooking oil, the use of large quantities of water alone, as extraction solvent, results in formation of soaps, then emulsions and further difficulties in process downstream. This problem does not exist in acid-catalyzed transesterification of waste cooking oil. The main objective of the current study was to evaluate the efficiency of other potential solvents, such as hexane and methanol, as well as water in a liquid-liquid extraction unit for separation of glycerol and biodiesel. In order to accomplish this task, first of all, the reliability of the UNIFAC activity coefficient model to predict the phase equilibria of such systems was evaluated. The technical feasibility of the use of hexane, methanol and water as solvents in a single-stage mixer-settler was then investigated. The biodiesel was produced via acid-catalyzed transesterification of waste cooking oil with methanol and the stream entering the mixer was assumed to be free of unconverted oil and acid catalyst, containing only biodiesel, glycerol and methanol. Furthermore, the biodiesel was assumed to have the properties of methyl oleate, which is the major component of biodiesel made from canola oil and methanol. The ASTM limit for glycerol content of biodiesel (<0.02 wt%), the residence time in the settler, the ratio of the liquid phase volumes in the settler and the biodiesel loss were the major performance measures considered. Four different solvent systems were found suitable: (1) water combined with residual methanol (with optimal mass ratio of biodiesel:methanol:water of 1:0.10:0.97), (2) a mixture of hexane and methanol (with optimal mass ratio of biodiesel:hexane:methanol of 1:1.15:1.62), (3) a mixture of hexane and water combined with residual methanol (with optimal mass ratio of biodiesel:hexane:methanol:water of 1:0.79:0.10:0.69) and (4) a mixture of hexane, methanol and water (with optimal mass ratio of biodiesel:hexane:methanol:water of 1:2.27:0.87:0.30). In acid-catalyzed production of biodiesel from waste cooking oil and methanol, the units located following the mixer-settler were designed and used in the economic evaluation of the entire biodiesel plant. The technically feasible solvent systems were then optimized based on maximizing the after-tax return on investment as a measure of the annual profitability. Although all the processes showed poor economic potentials with negative annual after-tax return on investment, the relative values were important to compare these processes. The biodiesel plants using hexane and water solvents combined with residual methanol or additional methanol with optimal biodiesel:hexane:methanol: water mass ratio of 1:0.43:0.10:0.24 or 1:2.19:0.90:0.34, respectively, yielded the highest annual after-tax return on investment of -35%. The process using water combined with residual methanol, with optimal mass ratio of biodiesel:methanol:water of 1:0.10:0.86 showed to be the least economically beneficial system, mainly because of its relatively low annual revenue and low total capital investment. In contrast, the process using water combined with residual methanol and the process using a mixture of hexane and water combined with additional methanol yielded the lowest and the highest biodiesel break-even prices of 1.70 and 1.91 $/L, respectively.

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Slaymaker, Elizabeth Ann. "Effects of surface active agents on drop size in liquid-liquid systems." Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/10260.

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Kanel, Jeffrey Scott. "Effects of some interfacial phenomena on mass transfer in agitated liquid-liquid dispersions." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/11257.

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Dickson, Philip James. "Gas liquid separation within a novel axial flow cyclone separator." Thesis, Cranfield University, 1998. http://hdl.handle.net/1826/3999.

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Cyclone separators have been described in detail and, although substantial research has been performed on solid / gas devices, the use of cyclones for gas / liquid separation has been comparatively ignored; this is particularly true for higher concentrations of liquid and for degassing applications. Consequently no generic models are available which will predict separation efficiency or pressure drop for all designs of cyclone. A novel design of axial flow cyclone called WELLSEP was examined for the purpose of degassing. This design was not believed to be optimal and no design criteria or performance prediction models were available for it. An experimental programme was therefore produced and executed to investigate changes in geometry and the affect of fluid dynamics. Changes to the length, vortex finder and swirl generator were examined first and then one design was selected and tested over a number of liquid flow rates, Gas Void Fractions (GVFs) and liquid extractions. Data was collected from the experiments which assisted in the development of semi-empirical models for the prediction of pressure drop and separation efficiency. These models could be used in the design of WELLSEP. Geometric and fluid dynamics changes have both been shown to influence the performance of the tested cyclone. The principal conclusions that have been drawn from this research are: " Of the tested designs, the design based upon a 30mm vortex finder diameter, settling chamber length of three times the diameter of the cyclone and a four start helix gave the optimum separation efficiency over the greatest range of conditions. 0 The separation efficiency is affected by the superficial liquid velocity and the liquid extraction but not the GVF. " The dimensionless pressure drop coefficient (Euler number) is a function of liquid extraction and GVF. It may also be a function of the superficial liquid velocity but it is unproven by this research.

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Babinchak, William Michael. "Pathological Aggregation and Liquid-Liquid Phase Separation of TDP-43 in Neurodegenerative Disease." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case158575494511376.

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Jordan, Alexander Thomas. "Liquid phase plasma technology for inkjet separation." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47543.

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Currently most deinking technologies are dependent upon flotation and dissolved air flotation (DAF) technology in order to separate inkjet ink from fiber and water. Much of this technology is based on ink that is extremely hydrophobic. This made flotation and DAF very easy to use because the ink in the water would very easily move with the air in flotation and be brought to the surface, after which the ink can be skimmed and the pulp can be used. Now that small scale printing has become the norm, there has been a move to high quality, small scale printing. This involves the use of a hydrophilic ink. Hydrophilic ink cannot be easily separated from water and fiber the same way the hydrophobic ink can be. With low concentrations of hydrophilic ink in the process water stream, it can be absorbed into the process but as the hydrophilic ink concentration rises alternative methods will be needed in order to separate inkjet ink from water. One solution is to find a method to effectively increase ink particle size. This will enable the ink particles to be filtered or to have an increase ecacy of removal during flotation. In this thesis, one solution is discussed about how electric field and electric plasma technologies can be used to increase particle size and help purify process water in recycle mills. This plasma treatment can very effectively bring ink particles together so that they may be separated by another method. There are two methods by which this may take place. One is polymerization and the other is electro-coagulation. These processes can work side by side to bring ink particles together. This plasma treatment process creates free radicals by stripping off hydrogen atoms from surrounding organic matter. These free radicals then react with the high alkene bond content within the ink to create a very large covalently bonded molecule. This is the new mechanism that is being investigated in this thesis. The other action that is taking place is electro-coagulation. Plasma treated ink can be filtered out using a cellulose acetate or cellulose nitrate membrane or they can be filtered using paper or fiber glass filters as well. The extent at which these can be filtered out is dependent on the size of the pores of the filter. In this study, it was shown that the plasma treatment was able to clean water with a fairly small amount of energy. It was also found that treatment time and concentration had very little eect on the outcome of the treatment ecacy. One factor that did have an effect was the pH. At very high pH values the process became noticeably less eective. The high pH essentially eliminated the electro-coagulation aspect of the treatment process and also hurt the polymerization aspect as well because of lower amount of hydrogen atoms available for the plasma to create free radicals. A model of the process was used to try to give the reader an idea of the ecacy that the process would have in an industrial scale process. The model assumes that two types of ink particles exist. One is ink that has a radical and another in which the ink does not have a radical. The model also assumes that if ink is at all polymerized, ink is filtered out with the 0.8 micron filter. The model assumes three reactions; initialization, propagation and partial termination. The partial termination is a result from the general chemical structure of ink. Ink has many double bonds in its general structure which makes termination very unlikely to occur, so the model assumes that on average when two radials interact that only one is eliminated. This model is only supposed to give the reader an idea of the ecacy of the process. The numbers provided in the model will change very significantly in a different system. The evidence behind polymerization aspect of the process comes from two main sources. One is the small molecule analysis from methanol after being exposed to the plasma and the other from the plasma being exposed to allyl alcohol. The small molecule analysis shows that the process generates free radicals on organic molecules. Methanol was exposed to the plasma and then the resulting GC/MS analysis showed that 1,2-ethanediol was present, this showed that the electric discharge process was able to create free radicals on organic molecules in the liquid phase. Using a similar process the plasma discharge process was exposed to a mixture of allyl alcohol, water and propanol and water in two separate experiments. The difference between these two molecules is an alkene bond that is between the carbon two and carbon three atoms. The particle size of both samples was then analyzed and it was shown that the solution with allyl alcohol had an average particle size about an order of magnitude larger than the solution with propanol in it. Because of all the evidence discussed here and in the rest of the thesis we believe that the plasma treatment of ink has both polymerization and electro-coagulation aspect. This process could also be a potential solution to the water soluble ink problem that will soon face the recycling industry.

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17

Dowling, P. D. "Optimisation of electrically augmented liquid phase separation." Thesis, University of Bradford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374913.

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Ng, Sin Yuan. "Gas-liquid separation using axial flow cyclones." Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419640.

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Yen, Pei-Shan. "Supported Liquid Metal Membranes for Hydrogen Separation." Digital WPI, 2016. https://digitalcommons.wpi.edu/etd-dissertations/480.

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Hydrogen (H2) and fuel cells applications are central to the realization of a global hydrogen economy. In this scenario, H2 may be produced from renewable biofuels via steam reforming and by solar powered water electrolysis. The purification required for fuel cell grade H2, whether in tandem or in situ within a catalytic reformer operating at 500 oC or above, would be greatly facilitated by the availability a cheaper and more robust option to palladium (Pd) dense metal membrane, currently the leading candidate. Here we describe our results on the feasibility of a completely novel membrane for hydrogen separation: Sandwiched Liquid Metal Membrane, or SLiMM, comprising of a low-melting, non-precious metal (e.g., Sn, In, Ga) film held between two porous substrates. Gallium was selected for this feasibility study to prove of the concept of SLiMM. It is molten at essentially room temperature, is non-toxic, and is much cheaper and more abundant than Pd. Our experimental and theoretical results indicate that the Ga SLiMM at 500 oC has a permeability 35 times higher than Pd, and substantially exceeds the 2015 DOE target for dense metal membranes. For developing a fundamental understanding of the thermodynamics and transport in liquid metals, a Pauling Bond Valence-Modified Morse Potential (PBV-MMP) model was developed. Based on little input, the PBV-MPP model accurately predicts liquid metal self-diffusion, viscosity, surface tension, as well as thermodynamic and energetic properties of hydrogen solution and diffusion in a liquid metal such as heat of dissociative adsorption, heat of solution, and activation energy of diffusion. The concept of SLiMM proved here opens up avenues for development practical H2 membranes, For this, improving the physical stability of the membrane is a key goal. Consequently, a thermodynamic theory was developed to better understand the change in liquid metal surface tension and contact angle as a function of temperature, pressure and gas-phase composition.

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Zou, Yiran. "Gas separation using supported ionic liquid membranes." Thesis, Queen's University Belfast, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517535.

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Bastos, Pedro David Anastácio de. "Separation of azeotropic mixtures using high ionicity ionic liquids." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/12208.

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Ola, Pius Dore. "Solvent extraction and liquid membrane containing ionic liquids and deep eutectic solvents for metal separation." Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13097323/?lang=0, 2018. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13097323/?lang=0.

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Ashrafizadeh, Seyed Nezameddin. "Solvent extraction and liquid membrane separation of rhodium." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37698.

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The aim of this work was to develop a viable solvent-extraction based system for the separation of rhodium (Rh) from aqueous chloride solutions. Ultimately, two different systems were developed. Kelex 100, a commercially available derivative of 8-hydroxyquinoline, was used as the extractant reagent in both of these systems. One of the systems involved the supported liquid membrane (SLM) extraction of Rh. In this system a very thin microporous "Gore-Tex" polymer sheet, impregnated with an organic solution of Kelex 100, served as the SLM. The other system involved the conversion of the chlorocomplexes of Rh to bromocomplexes prior to their solvent extraction with Kelex 100.
The results of the lab-scale experiments using a SLM of Kelex 100 having a surface area of 44 cm2 are reported. The optimum conditions for Rh permeation were found as a feed solution of 2.5 M HCl and a strip solution of 0.1 M HCl. The SLM was quite stable at the optimum conditions with no sign of organic loss or membrane deterioration after 72 hours of operation. It was determined that the HCl activity gradient across the membrane acts as the driving force that "pumps" the non-aquated Rh chlorocomplexes against their concentration gradient. The mechanism of Rh permeation was the ion-pair formation between the protonated Kelex 100 and RhCl6 3- complexes. The rate of Rh permeation was in the order of 10-6 mol.m-2.s-1. The mechanism of HCl and H2O permeation, which were co-extracted along with Rh chlorocomplexes, were found to be the hydration of protons at the low feed acid region and the formation of microemulsions at the high feed acid region. The permeated acid and water were separated from the SLM receiving phase by contacting the latter phase with an organic solution of trioctylamine (TOA). The chlorocomplexes of Rh(III) and acid are readily extracted to the TOA organic phase and subsequently subjected to differential stripping with a concentrated solution of Cl- and a mild NaOH solution, respectively. By interfacing the TOA solvent extraction with the SLM of Kelex 100 highly concentrated solutions of Rh (at least 10 times the initial concentration) and raffinates essentially free of rhodium were produced.
The UV-Visible investigations revealed that the bromocomplexes of Rh undergo aquation to a much lesser extent than that of the chlorocomplexes. The chlorocomplexes of Rh were converted to bromocomplexes by precipitating first the Na(NH4)2Rh(NO2)6 salt and subsequently dissolving that in an HBr solution. The newly formed bromocomplexes of Rh(III) responded very favorably to extraction with Kelex 100. Relatively high distribution coefficients, about 20, and very steep extraction isotherms were generated. The freshly loaded Kelex 100 organic was efficiently stripped upon contact with a strip solution of 6--8 M HCl and a contact time of 10--12 hours. The developed system shows high promise from a practical implementation point of view.

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Yi, Ling. "Micellar liquid chromatographic separation of polycyclic aromatic hydrocarbons /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426117.

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Wang, Ying. "Chiral ionic liquid in chiral separation and catalysis." Thesis, Queen's University Belfast, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603555.

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In this thesis, the results of synthesis of chiral ionic liquids (ILs) and an investigation of their application in chiral separation and catalysis are described. The study of the chiral lLs application was performed using liquid-liquid extraction, crystallization and asymmetric catalysis with analysis of substrate content and enantioselectivity by High Performance Liquid Chromatography (HPLC) . A series of chiral lLS with chiral cations or chiral anions were synthesized through alkylation or anion exchange with optical pure starting materials as the •chiral pool", Properties of chiral ILS made in house were studied using various techniques, The structures and configurations of the chiral ILs can be altered easily to meet the required physical properties, such as melting point and viscosity, Chiral! ILs made in house show chiral affinity with a range of racemic compounds, In the liquid-liquid extraction of menthol from chiral lL, good extraction is observed from the chiral lL layer into alkane !layer without visible leaching of the chiral lL into the alkane layer. In the mandelic acid resolution by • Dutch resolution", 22 different ILS were used as additive in the chiral selector, In general, ILS exhibit a equalize effect on both yield and ee of the final product. For the asymmetric catalysis study, both Mukaiyama-aldol reaction and Diels-Alder reaction were investigated with Cu(II)-PhBOX and Zn(II)-PhBOX as catalyst. In the Mukaiyama-aldol reaction, chiral ILS can be applied . as ligand and an increased ee is observed as compared with the reactions in the absence of the Il. In the Diels-Alder reaction, addition of the chiral Il 19 (Il of (1R,2S.5R)- menthol) with Zn(II)-PhBOX led to an increase in the endo ee from 5 % in DCM, 68 % in ether and 57 % in pure (C 2mim][NH 10 91 % under homogeneous reaction condition and 95 % in biphasic system with both high conversion and high endo selectivity. The endo selectivity of biphasic system with the chiral lL 1 g, [C2mim][NTf21 and ether is 99 %, which means nearly all product goes into endo form with 95 % ee.

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Allstaff, E. J. "Gas/liquid separation in an I-SEP cyclone." Thesis, Cranfield University, 2002. http://dspace.lib.cranfield.ac.uk/handle/1826/10724.

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An extensive experimental programme tested an l-SEP unit with air and water. This provided data on the separation efficiency and pressure drop across the l- SEP, as they varied with changing inlet conditions, geometry and outlet restrictions. The main conclusion from this work is that the resistance on the outlets directly affects the efficiency of the separator. Although it is possible to optimise the performance by changing 'the geometry, a small change in inlet conditions, common in oil and gas applications, causes the performance to change. _By using an identified relationship between the differential pressure and the operating conditions, an optimum performance over a much wider range of inlet conditions can be achieved. This work has contributed to the field of gas/liquid separation in axial-flow cyclones by demonstrating that manipulating the differential pressure between the outlets can control the separation efficiency. The relationship developed between the optimum differential pressure and the inlet conditions has not been identified in any of the literature available at the time of this work.

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Jegede, Oluwatoyin Enitan. "Metastable liquid phase separation in Co-Cu alloys." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/19808/.

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Two Co – Cu alloys were studied by drop tube processing technique in a view of investigating the effects of rapid solidification on the phase transformations and microstructural evolution in the metastable alloys. The as – solidified samples had diameters ranging from 53 – 850+ μm and these were analysed using various characterization techniques such as optical (OM) and scanning electron (SEM) microscopy, x- ray diffraction (XRD) and differential thermal analysis (DTA). The Cu – 50 at. % Co alloy was observed to experience liquid phase separation at lower undercooling than the Cu – 68.5 at. % Co alloy. This is found to be in accordance to the asymmetrical metastable miscibility gap determined for the alloy system. Significant number of liquid phase separated structures were observed at cooling rates in excess of 15000 Ks-1, evidenced by a range of microstructural morphologies including stable core shell structures, evolving core shell structures and structures in which the demixed liquid phases were randomly distributed. A large number of these structures experienced multiple liquid phase separation processes. The configuration of the core shell structures were found to be independent of the composition of phases and their relative abundance, with the core always formed by the higher melting point phase. The optimum production of the core shell structures were found to be a function of cooling rate.

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Allstaff, Ewan James. "Gas/liquid separation in an I-SEP cyclone." Thesis, Cranfield University, 2002. http://dspace.lib.cranfield.ac.uk/handle/1826/10724.

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An extensive experimental programme tested an l-SEP unit with air and water. This provided data on the separation efficiency and pressure drop across the l- SEP, as they varied with changing inlet conditions, geometry and outlet restrictions. The main conclusion from this work is that the resistance on the outlets directly affects the efficiency of the separator. Although it is possible to optimise the performance by changing 'the geometry, a small change in inlet conditions, common in oil and gas applications, causes the performance to change. _By using an identified relationship between the differential pressure and the operating conditions, an optimum performance over a much wider range of inlet conditions can be achieved. This work has contributed to the field of gas/liquid separation in axial-flow cyclones by demonstrating that manipulating the differential pressure between the outlets can control the separation efficiency. The relationship developed between the optimum differential pressure and the inlet conditions has not been identified in any of the literature available at the time of this work.

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Zhang, Liqin. "A new liquid-liquid partitioning system for bioseparations at low temperatures." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1184618209.

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Eliasson, Anders. "Liquid phase sintering of W-Ni-Fe composites : liquid penetration, agglomerate separation and tungsten particle growth." Doctoral thesis, KTH, Keramteknologi, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3870.

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The initial stage of liquid phase sintering, involving liquid penetration, agglomerate separation, particle spreading and growth has been investigated in experiments using tungsten heavy alloys. The particle composites used were produced by hot isostatic pressing (HIP) of pure powder mixtures of W-Ni-Fe-(Co). By using different HIP temperatures, volume fractions of tungsten, alloying elements like Cobalt and Sulphur or excluding Iron from the matrix, liquid penetration, agglomerate separation and particle growth conditions were affected. The investigations were performed mainly under microgravity (sounding rockets or parabolic trajectories by airplanes) but at high tungsten particle fractions, short sintering times or at infiltration of solid pure tungsten, they were performed at normal gravity. The liquid penetration of the tungsten agglomerates is explained by initial wetting under non-equilibrium conditions, due to the reaction between the liquid matrix and the particles, and a decrease of interfacial energy. The dissolving of tungsten gives a pressure drop in the penetrating liquid and a driving force for the liquid movement by a suggested parabolic penetration model. For cold worked tungsten, a penetration theory was proposed, where an internal stress release in the penetrated tungsten grains creates space for the advancing liquid. The spreading of the tungsten agglomerates is explained by an interagglomerate melt swelling due to a Kirkendall effect. The liquid matrix undergoes a volume increase since the diffusion rates of Ni-Fe are higher than for W and initial concentration gradients of W and Ni, Fe exists. The suggested model by Kirkendall are also used for an analysis of the interaction behaviour between solid particles and a solidification front and inclusion behaviour in iron base alloys during teeming and deoxidation. The average tungsten particles size decrease initially since part of the tungsten particles is dissolved when the non-equilibrium matrix phase is melting. When equilibrium is reached, the tungsten particles grow in accordance with the Ostwald ripening process by an approximately 1/3 power law. Larger particle fraction of particles showed a higher growth rate, due to shorter diffusion distances between the particles. Cobalt, Sulphur and absence of iron in the matrix were found to increase the growth rate of the tungsten particles due to a higher surface tension between the solid tungsten particles and the matrix melt.
QC 20100528

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31

Allard, Erik. "Metabolic Studies with Liquid Separation Coupled to Mass Spectrometry." Doctoral thesis, Uppsala universitet, Analytisk kemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-110310.

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Metabolism is the sum of all chemical processes with the purpose to maintain life, as well as enable reproduction, in a living organism. Through the study of metabolism, increased understanding of pharmacological mechanisms and diseases can be achieved. This thesis describes several ways of doing so, including targeted analysis of selected metabolites and investigations of systematic metabolic differences between selected groups through pattern recognition. A method for exploring metabolic patterns in urine samples after intake of coffee or tea was developed. The methodology was later used with the aim to find biomarkers for prostate cancer and urinary bladder cancer. Furthermore, a fully automated quantitative method was developed for concentration measurements of the double prodrug ximelagatran and its metabolites in pig liver. The method was then used to study the roll of active transporters in pig liver cells. Moreover, a fundamental study was conducted to investigate how monitoring of small, doubly charged analytes can improve the limit of detection and precision in a quantitative method. The techniques used for the experiments were liquid separation coupled to electrospray mass spectrometry. Extra efforts were made to make the separation and the ionization as compatible as possible to each other for increased quality of the collected data.

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Etuk, Benjamin Reuben. "Separation of alcohol from beer by liquid membrane technique." Thesis, Heriot-Watt University, 1988. http://hdl.handle.net/10399/984.

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Lifsey, Karen Marie. "Liquid crystal polymers : a unique class of separation media." Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365163.

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Meeson, Stephen Russell. "The separation of enantiomers by high performance liquid chromatography." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278414.

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Rocco, Anna. "Separation of Enantiomers by Means of NanoO-Liquid Chromatography." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20130122_144808-59559.

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Nano-liquid chromatography (nano-LC) was selected as analytical tool to develop different methods for chiral separations. Nano-LC offers several advantages over conventional LC, e.g., low sample requirement, short analysis time, easy coupling with mass spectrometer, and use of small amount of reagents, with a consequent low environmental pollution. In case of chiral separations, where expensive chiral stationary phases or chiral mobile phase additives (CMPA) have to be employed, nano-LC results very useful since it allows to perform analysis with small amount of this costly material. Initially, a derivatized β-cyclodextrin, heptakis (2,3,6-tri-O-methyl)-β-cyclodextrin, was employed as CMPA for the chiral separation of some non steroidal anti-inflammatory drugs. The role of different achiral stationary phases in the separative process was investigated. The employed capillary columns were packed in the laboratory, following the slurry-packing procedure. Subsequently, the performance of a reversed phase C18 particulate packed column was compared with that one of a C18 monolithic column, in combination with cyclodextrins (heptakis (2,3,6-tri-O-methyl)-β-cyclodextrin or hydroxypropyl--cyclodextrin) as CMPA. Finally, hydroxypropyl--cyclodextrin was selected as chiral selector to prepare chiral monolithic columns by one-step synthesis. For this aim, the cyclodextrin was activated as the allyl derivative. The composition of the polymeric mixture of the continuous beds was varied... [to full text]
Skysčių nano-chromatografija buvo pasirinkta kaip įrankis kurti įvairius chiralinių junginių atskyrimo metodus. Skysčių nano-chromatografija turi eilę privalumų, lyginant su tradiciniais skysčių chromatografijos metodais, pvz.: mažą bandinio poreikį, trumpą analizės trukmę, suderinamumą su masės spektrometrija ir nedideles tirpiklių, reagentų sąnaudas, todėl mažą aplinkos taršą. Chiralinių junginių analizei atlikti, kai reikalingos brangios chiralinės nejudrios fazės ar chiraliniai judrios fazes priedai, skysčių nano-chromatografija yra ypač naudinga, nes leidžia atlikti analizę su minimaliomis šių brangių medžiagų sąnaudomis. Pirmiausia, derivatizuotas β-ciklodekstrinas, heptakis (2,3,6-tri-O-metil) - β-ciklodekstrinas, buvo panaudotas kaip chiralinis nejudrios fazes priedas kai kurių nesteroidinių priešuždegiminių vaistų enantiomerams atskirti. Buvo įštirtas įvairių achiralinių nejudrių fazių vaidmuo atskyrimo procese. Šiuo tikslu naudojant suspensinį birių dalelių pakavimo metodą laboratorijoje buvo paruoštos kapiliarinės kolonėlės. Vėliau, buvo lyginama C18 biriais sorbentais pakrautų atvirkštinių fazių ir monolitinių kapiliarinių kolonėlių skiriamoji geba, chralinias judrios fazes priedais naudojant ciklodekstrinus (heptakis (2,3,6-tri-O-metil)-β-ciklodekstriną arba hidroksipropil-β-ciklodekstriną). Galiausiai, vienpakopės polimerizacijos būdu buvo gautos chiralines kapiliarines kolonėles, chiralniu selektoriumi naudojant hidroksipropil-β-ciklodekstriną. Šiuo tikslu... [toliau žr. visą tekstą]

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36

Fukuda, Junichi. "Phase Separation of Liquid Crystalline Polymers -Statics and Dynamics-." 京都大学 (Kyoto University), 1999. http://hdl.handle.net/2433/157171.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである
Kyoto University (京都大学)
0048
新制・課程博士
博士(理学)
甲第7631号
理博第2016号
新制||理||1081(附属図書館)
UT51-99-G225
京都大学大学院理学研究科物理学・宇宙物理学専攻
(主査)教授小貫明, 教授蔵本由紀, 教授吉川研一
学位規則第4条第1項該当

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37

JAIN, ABHISHEK. "DEVELOPMENT OF MEMBRANES FOR LIQUID PHASE ETHANOL-WATER SEPARATION." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1109038241.

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38

Lin, Han. "GRAPHENE OXIDE-BASED MEMBRANE FOR LIQUID AND GAS SEPARATION." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1595260029225206.

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39

Wang, Shujun. "Liquid-liquid phase separation in an isorefractive polyethylene blend monitored by crystallization kinetics and crystal-decorated phase morphologies." Akron, OH : University of Akron, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1226680911.

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Dissertation (Ph. D.)--University of Akron, Dept. of Polymer Science, 2008.
"December, 2008." Title from electronic dissertation title page (viewed 12/29/2008) Advisor, Stephen Z. D. Cheng; Committee members, Alexei Sokolov, Darrell H. Reneker, Gustavo A. Carri, Thein Kyu; Department Chair, Ali Dhinojwala; Dean of the College, Stephen Z. D. Cheng; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.

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40

Marsden-Jones, Siân Catherine. "The application of quantitative structure activity relationship models to the method development of countercurrent chromatography." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/12598.

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A fundamental challenge for liquid-liquid separation techniques such as countercurrent chromatography (CCC)and centrifugal partition chromatography (CPC), is the swift, efficient selection of the two phase solvent system containing more than two solvents, for the purification of pharmaceuticals and other molecules. A purely computational model that could predict the optimal solvent systems for separation using just molecular structure would be ideal for this task. The experimental value being predicted is the partition coefficient (Kd), which is the concentration of the compound in one phase divided by the concentration in the other. Using this approach, Quantitative Structure Activity Relationship (QSAR) models have been developed to predict the partitioning of compounds in two phase systems from the molecular structure of the compound using molecular descriptors. A Kd value in the range of 0.5 to 2 will give optimal separation. Molecular descriptors are varied, examples include logP values, hydrogen bond donor values and the number of oxygen atoms. This work describes how the QSAR models were developed and tested. A dataset of experimental logKd values for 54 compounds in six different combinations of four solvents (heptane, ethyl acetate, methanol and water) was used to train the QSAR models. A set of 196 possible molecular descriptors was generated for the 54 compounds and a partial least squares regression was used to identify which of these was significant in the relationship between logKd and molecular structure. The resulting models were used to predict the logKd values of four test compounds that had not been used to build the QSAR models. When these predictions were compared to the experimental logKd values, the root mean squared error for four of the six models was less than 0.5 and less than 0.7 for the remaining two. These models were used to successfully separate a range of structurally diverse pharmaceutical compounds by predicting the best solvent systems to carry out the separation on the CCC/CPC using nothing but their molecular structure.

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Ortega-Rivas, Enrique. "Dimensionless scale-up of hydrocyclones for separation of concentrated suspensions." Thesis, University of Bradford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253983.

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42

Schütz, Stefan [Verfasser], and Remco [Akademischer Betreuer] Sprangers. "Liquid-Liquid Phase Separation: Molecular Mechanism and Influence on the mRNA Decapping Machinery / Stefan Schütz ; Betreuer: Remco Sprangers." Regensburg : Universitätsbibliothek Regensburg, 2020. http://d-nb.info/1219301094/34.

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43

Wang, Shujun. "Liquid-Liquid Phase Separation in an Isorefractive Polethylene Blend Monitored by Crystallization Kinetics and Crystal-Decorated Phase Morphologies." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1226680911.

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44

Palud, Amandine. "Liquid-liquid phase separation mediated by low complexity sequence domains promotes stress granule assembly and drives pathological fibrillization." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066560/document.

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Il a été observé que l’altération des fonctions des granules de stress, entités cytoplasmiques non-membranaires composées d’ARN et de protéines liant l’ARN (RBPs), peut conduire au développement de maladies telles que la sclérose latérale amyotrophique, la démence fronto-temporale, la myopathie à inclusions et la maladie de Paget des os. Ces pathologies sont caractérisées par un dépôt cytoplasmique d’inclusions solides enrichies en RBPs et comprenant des fibrilles. Une connexion génétique a été suggérée entre la persistance des granules de stress et l’accumulation de ces inclusions pathologiques dans le cytoplasme des patients. Dans mon manuscrit de thèse, il est mis en évidence le fait que la protéine hnRNPA1, dont les mutations entrainent les maladies mentionnées plus haut, subit une séparation de phases entre deux liquides connue également sous l’appellation « Séparation de Phases Liquide-Liquide » (LLPS) dans des gouttelettes enrichies en protéines. Bien que le domaine composé d’une séquence à faible complexité (Low Complexity sequence Domains ou LCD) soit suffisant pour obtenir cette séparation de phases, les domaines de liaison à l’ARN y contribuent également en présence d’ARN. Cela a permis d’envisager l’existence de plusieurs mécanismes intervenant dans la régulation de l’assemblage de ces granules. Un autre résultat a mis en exergue le fait que la formation de fibrilles n’est pas une obligation pour permettre la séparation de phases mais que les gouttelettes, enrichies en protéines, entrainent, par ailleurs, une augmentation de la formation de ces fibrilles. La séparation de phases liquide-liquide induite par le domaine composé d’une séquence à faible complexité semble contribuer à l’assemblage des granules de stress et à leurs propriétés liquides. Finalement, cette étude propose d’établir une réelle corrélation entre la formation des granules de stress qui deviennent persistants et l’accumulation d’inclusions pathologiques dans le cytoplasme des patients
Stress granules are membrane-less organelles composed of RNA-binding proteins (RBPs) and RNA. Functional impairment of stress granules has been implicated in amyotrophic lateral sclerosis, inclusion body myopathy, Paget’s disease of bone and frontotemporal dementia; these diseases are characterized by solid, fibrillar, cytoplasmic inclusions that are rich in RNA binding proteins (RBPs). Genetic evidence suggests a link between persistent stress granules and the accumulation of pathological inclusions. In this thesis manuscript, I demonstrate that the disease-related RBP hnRNPA1 undergoes liquid-liquid phase separation (LLPS) into protein-rich droplets mediated by a low complexity sequence domain (LCD). While the LCD of hnRNPA1 is sufficient to mediate LLPS, the folded RNA recognition motifs contribute to LLPS in the presence of RNA, potentially giving rise to several mechanisms for regulating assembly of stress granules. Importantly, while not required for LLPS, fibrillization is enhanced in protein-rich droplets. I suggest that LCD-mediated LLPS contributes to the assembly of stress granules and their liquid properties, and provides a mechanistic link between persistent stress granules and fibrillar protein pathology in disease

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Brigadeau, Alexandre H. M. "Modeling and Numerical Investigation of High Pressure Gas-Liquid Separation." Doctoral thesis, Norwegian University of Science and Technology, Department of Energy and Process Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1756.

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In this Ph.D. thesis, a model for the study of the efficiency of high-pressure liquid/gas industrial separators has been developed. The model is a three fluid model (gas phase, droplet phase and film phase) and is entirely Eulerian. For the gas phase, a κ - ε model extended to multiphase flows has been used. The turbulent kinetic energy of the dispersed phase, the turbulent dispersion coefficient and the momentum equation of the liquid film were closed algebraicly. The total deposition velocity was determined by turbulent dispersion and a near-wall deposition velocity. The latter was the sum of a non-diffusive term (due to the mean convection of the flow and gravity) and a diffusive term. This diffusive term accounted for the diffusion-impaction deposition regime and the inertia-moderated deposition regime. The gas/liquid film interfacial shear stress was calculated from the local value of the turbulent kinetic energy of the gas. The film acted on the gas as a steady rough wall. An experimental entrainment rate correlation was chosen. The model was implemented in a finite-volume commercial code (Fluent 6.2). The model is based on local closure relations so that it can be further developed for complex industrial geometries.

The results were first compared with experiments from the literature. Deposition rates and film heights were in agreement with the data of the literature. However, the calculated pressure drops were higher and the calculated entrainment rates were lower than the experimental values. The present work pinpoints the reasons of these inaccuracies and corrections to the original model are proposed. The model was finally applied to calculate the efficiency of a vane-pack demister. At atmospheric pressure with air and water the efficiency of the demister was 99.7%. This value agrees with the prediction of a former model from the literature. At high pressure with natural gas and condensate the efficiency of the separator was 0%. The deposition rate was lower, the entrainment rate very high and the liquid layer vanished.

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Adechy, Didier. "Phase separation in annular gas-liquid flows at t-junctions." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251963.

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Hamzah, Mohd Suhaimi. "Separation and determination of lanthanides by high performance liquid chromatography." Thesis, University of Salford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308131.

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Philibert, Gwenaelle Sophie. "Improved Separation of Biological Compounds Using Enhanced-Fluidity Liquid Chromatography." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322479367.

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Cao, Zishu. "Colloidal Zeolite Supported Ionic Liquid Membranes for CO2/N2 Separation." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1406821911.

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50

Lizon, Tatiana Gallego. "Cadmium separation from phosphoric acid using the emulsion liquid membrane." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/7634.

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An emulsion liquid membrane (ELM) containing Cyanex 302 has been successfully used for the recovery of cadmium from synthetic phosphoric acid solutions containing 30% wt. P205. The ELM formulation was optimised for high extraction rate and stability. Cyanex 302, and a mixture of NaC1 (3M) and HC1 (1M), were selected from a set of possible reagents and stripping phases, following equilibrium and kinetic experiments in two-phase systems. Under chemical control the rate of Cd2 extraction was pseudo first order with respect to Cd2 and Cyanex 302 concentration. Arlacel C was found to be the most suitable surfactant for emulsion stability. The dependence of the ELM rate of Cd 2 extraction on the concentrations of cadmium, Cyanex 302, and surfactant, as well as on phase and treat ratio, and homogeniser and stirrer speed, was investigated. Cadmium extraction levels were found to be above 90% for most conditions. The influence of operating variables on emulsion swelling and rupture was also evaluated as a function of time. Swelling of the internal phase of the emulsion reached values greater than 50%, whilst emulsion rupture was below 2%. Emulsion globule size distributions in the stirred tank were measured for different impeller speeds and diameters, reagent concentrations, and emulsion hold-up, using an endoscope attached to a high-speed video camera. A correlation for globule size, accounting for swelling and rupture phenomena, changes in viscosity and hold-up, was proposed and found to be in good agreement with experimental results. This allowed the effect of the stirring speed on the specific interfacial area and the mass transfer coefficient to be decoupled, and led to the conclusion that the overall rate of Cd 2 recovery was controlled by diffusional resistances in the continuous phase. A time- dependent model, and a quasi-steady state model were proposed for the extraction of cadmium with the ELM. Simulations with both models were found to be in good agreement with experimental results.

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Dissertations / Theses on the topic 'Liquid/liquid separation'

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