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GEOPOLYMERS WITH GREEN LIQUOR DREGS : An investigation of the possibility tomanufacture a geopolymer based on residual streamsSundqvist, Martin January 2021 (has links)
The pulp and paper industry make up a large part of the Swedish industry and is alsogrowing worldwide. With its growth, the amounts of residuals that are produced alsoincrease. The estimated annual global amount of residuals generated from pulp millsexceeds 1 million tons. The residuals include fly ash (FA) and green liquor dregs(GLD), which can cause harm to the environment as well as to the human health ifnot taken care of properly. Therefore, new, sustainable uses for these residual streamsare in strong need to be found. The construction sector is one of the most energy-intensive and CO2-emitting sectorssince ordinary Portland cement (OPC) is one of the most manufactured materials inthe world and causes large amounts of CO2 emissions when produced. Research hasfocused on reducing the CO2 generated by OPC. One approach is to include FA andGLD in a so-called geopolymer, which is a cementitious material formed when aninorganic material rich in aluminium (Al) and silicon (Si) reacts with an alkalineactivator such as sodium hydroxide (NaOH). A strong geopolymer including FA andGLD would not only create a use for these residuals, but it would also be a lessenergy craving alternative to concrete. Using FA and GLD from the Metsä Board pulp mill in Husum in various proportions,this study aimed for creating a geopolymer that is suitable as a construction material.The composition of the geopolymer blends differed depending on the proportions ofGLD and FA added, as well as regarding the water contents of the blends, and thequantity of alkaline activator solution added. The compositions also varied regardingthe addition of kaolin, an additional aluminosilicate source. Lignosulfonate, a ligninbasedproduct from the sulfite pulping industry was also evaluated as an additive dueto its water-reducing properties when used in concrete. The geopolymers wereevaluated in terms of blend workability and by uniaxial compressive strength (UCS)tests after 7 and 28 days of curing. The strongest geopolymer, in which GLD constituted 20 wt.% of the dry components(sand and alkaline chemicals excluded), endured a pressure of 2.3 MPa after 28 daysof curing. Increasing the water content made the geopolymer blend more workable,but also resulted in a UCS decrease of the geopolymer. Addition of cement to themixture and an increased quantity of alkaline activator solution both resulted in alower UCS as well. Compared to cement mortar (20 MPa at the 7th curing day) andliterature values of other geopolymers, the strengths of the manufacturedgeopolymers were low overall (0.4–1.4 MPa at the 7th curing day). One reason for thelow UCS could be the use of kaolin instead of a more reactive aluminosilicate source.Moreover, the FA showed to have low Si and Al contents, which can affect thegeopolymer strength. Further investigations are needed to develop a strongergeopolymer.
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Biomimetically improved materials comprising microfibrillated celluloseByström, Cornelia January 2021 (has links)
Microfibrillated cellulose (MFC) is a renewable, cellulosic material mainly producedfrom wood fibers, which are found in the secondary cell walls of plant cells. With theincreased demand for renewable biopolymer films in packaging, MFC has emerged asa potential alternative to non-renewable polymer films. However, some obstacles forachieving a highly ductile material that also possesses sufficient barrier propertiesremain. Bacterial cellulose (BC) is a source of nanocellulose that has been reported tohave higher purity, higher flexibility, and better water-absorption capacity and tensilestrength than plant-derived cellulose. One source of BC is from the production ofKombucha, where BC is produced by acetic acid bacteria in a "Symbiotic Culture OfBacteria and Yeast", generally referred to as SCOBY. During SCOBY fermentation, amulti-layered biofilm will form on the air-medium interface. The film consists ofmicrofibrillated bacterial cellulose of high purity and mechanical strength. In thisstudy, the objective was to find out how mechanical properties of a film made ofmicrofibrillated cellulose can be improved by learnings obtained from investigatingthe properties and composition of a film made from SCOBY cellulose. Characterization of the intrinsic properties of washed and unwashed SCOBY wasperformed by using field emission scanning electron microscopy (FE-SEM), Fouriertransforminfra-red (FTIR) spectroscopy, and moisture uptake analysis. Gaschromatography - mass spectrometry (GC-MS) was utilized to examine the presenceof potential plasticizing compounds from the fermentation. Uniaxial tensile testingwas performed on MFC films plasticized with discovered fermentation products toanalyze their impact on the mechanical properties of MFC, such as strain-at-break andE modulus. Additionally, to evaluate how washed and unwashed BC from SCOBYpotentially could be incorporated into MFC films to improve ductility, a study on theeffect of fluidization was performed. The characterization confirmed the high purity of washed SCOBY and the high waterabsorptioncapacity of unwashed SCOBY. GC-MS of dry SCOBY revealed thepresence of hydrophilic compounds from the fermentation with potential to act as biobasedplasticizing agents in SCOBY cellulose. Glycerol and another compound foundin dry SCOBY were tested for their plasticizing properties in MFC films. Glycerolwas found to increase the strain-at-break for MFC films with 181%. The other studiedcompound also improved the ductility of the MFC material. Thereby, a newapplication of this compound was discovered. From the fluidization study, uniaxialtensile testing revealed a strain-at-break of (10.5 ± 0.4) % and E modulus of (10500 ±1140) MPa for MFC films containing 10% washed SCOBY material. Thiscorresponds to an increase in strain-at-break of 402% compared to pure MFC films(2.09 ± 0.42), successfully improving the ductility. The results from this study areplanned to be used as a basis for further studies in the area of bio-based packaging.
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The encapsulation of Ubiquinone-10 in different lipid nanocarriersÅngström, Molly January 2020 (has links)
No description available.
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LMCA1 as prototype system for the study of Ca2+ pumps in nanodisksMagkakis, Konstantinos January 2021 (has links)
Membrane proteins make up approximately a third of all proteins and serve as prime drug targets, yet their structural and biophysical characterization presents some unique challenges due to their hydrophobic surfaces and flexible structure. The main goal of this project was to compare, with the use of activity assays, two methods employed for the experimental handling of membrane proteins. The methods compared were the traditional method of using detergent micelles to keep the membrane proteins in solution, with the novel technique of reconstituting the proteins in nanodisks, using the LMCA1 P-type ATPase as a prototype. The secondary goal was to successfully express, purify and reconstitute in nanodisks, an inactive mutant of the LMCA1 protein to use as a control for the activity measurements. As of the end of this project the inactive LMCA1 mutant was successfully reconstituted into MSP1D1 nanodisks and the initial assay results showed higher activity for the reconstituted protein. This points to the conclusion that nanodisks could provide an environment that is more native for the protein, compared to detergent micelles, which can lead to greater precision in their structural and biophysical characterization.
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Selective Inhibition of Metacaspase 4 in Arabidopsis ThalianaAndersson, Thilde January 2021 (has links)
Metacaspases are a recently discovered family of cysteine-dependent proteases present in plants, fungi, and lower eukaryotes. They are believed to be involved in regulated cell death in non-metazoan cells, but little is known about their distinct functional properties. Metacaspases have been identified in various forms of protozoa that cause pathogen-induced diseases, which affect millions of people every year. Their biological function in protozoa and their absence in the human host make them an attractive drug target for treatment of such diseases. In this project, we have explored a potential hit towards metacaspase 4 in Arabidopsis Thaliana. The hit compound was successfully identified from high throughput screening, and an initial structure-activity relationship was established by testing a set of synthesized analogues towards the enzyme. The compounds were also tested against metacaspase 9 in Arabidopsis thaliana, where no inhibitory activity was observed. The active site is highly conserved between the different clades of metacaspases, and these results suggest that the hit compound interacts with an allosteric site on the target. The results presented here provide important information on how selective regulation of metacaspases can be achieved by developing small chemical probes, targeting allosteric sites on the enzyme. Hopefully, this can be applied to other metacaspases systems to evaluate their biological function in protozoa.
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Impact of Water on Recycling Lithium Ion Battery Cathode Material in a Deep Eutectic SolventÖstlund, Erik January 2020 (has links)
No description available.
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Mechanochemistry : C-H arylation and annulative π-extension reactions attempted inball millLjungkvist, Oskar January 2018 (has links)
No description available.
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Influence of divalent cations on extraction of organic acids in coffeeBratthäll, Tove January 2021 (has links)
No description available.
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Quantitative NMR spectroscopy on fluorine-containing drugs - a comparative study on pharmaceutical raw materials and different dosage formsMohamadi, Khonaw January 2020 (has links)
Nuclear Magnetic Resonance (NMR) is a technique with several advantages, such as high rapidity and easy operation as no sample specific standard or sample derivatization is required. Proton NMR is the most common NMR experiment, since hydrogen is “NMR active” and present in most organic compounds. Because of this, there is a high risk of overlapping signals in 1H-NMR spectra in samples containing multiple components, e.g. pharmaceutical preparations. Since Fluorine (19F) is “NMR active”, but not as common in organic molecules as hydrogen, peak overlapping is unlikely. A quantitative 19F-NMR method was therefore developed in this study. Certain parameters (number of scans, relaxation delay, excitation frequency, pre-scan delay, spectral width & pulse angle) were examined during the method development, based on samples containing fludrocortisone acetate and 4,4´-difluorobenzophenone. For evaluation of the developed method, experiments were set up with different active pharmaceutical ingredients as well as pharmaceutical products. Good linearity and precision was obtained, and conclusions from the research experiments are that the developed method gives reliable purities compared to the reference method 1H-qNMR, and can therefore be used to achieve estimated assays on pharmaceutical raw materials. The method is also applicable on analysing registered pharmaceutical products as well as determining whether the strength of a suspected illegal drug is within the therapeutic range or not. Finally, the range of the method was determined to approximately 1-20 mg/mL, if examined on a 300 MHz NMR instrument.
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Occurrence and fate of 7 APIs in two sewage treatment plants - and their reactions to tertiary treatmentBoström, Sara January 2020 (has links)
In recent years concerns have been raised about micropollutants, such as pharmaceutical ingredients, being released into the aquatic environment. As a consequence, signs of adverse effects on biota have been identified. Also, potable drinking water is a precious and potentially finite resource that need be taken care of. Sewage treatment plants have been identified as point sources for emissions of micropollutants originating from modern way of life. The problem is that the sewage treatment plants of today are not built to handle these kinds of pollutants. One possibility is however to supplement existing processing equipment with new technology to overcome that deficiency. In this thesis, the ability, of two sewage treatment plants, to remove seven active pharmaceutical ingredients of different structure and class have been investigated. All seven were found in at least one of the influent samples and only one was removed to any significant level in one of the treatment plants. Effluent samples were then subjected to tertiary treatment by ozonation, activated carbon or biochar to investigate the possibility of further reducing the concentrations in the effluent. Activated carbon proved to be very efficient and to some extent ozone. However, ozonation trials were inconclusive due to contamination of samples.
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