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Mass Spectrometry of Biologically Active Small Molecules : Focusing on polyphenols, alkaloids and amino acidsSpáčil, Zdeněk January 2010 (has links)
The foci of this dissertation are on advanced liquid chromatography (LC) separation and mass spectrometry (MS) techniques for the analysis of small bioactive molecules. In addition to discussing general aspects of such techniques the results from analyses of polyphenols (PPs), alkaloids and amino acids published in five appended studies are presented and discussed. High efficiency and well understood principles make LC the method of choice for separating analytes in many kinds of scientific investigations. Moreover, when LC is coupled to an MS instrument, analytes are separated in two stages: firstly they are separated and pre-concentrated in narrow bands using LC and then separated according to their mass-to-charge (m/z) ratios in the MS instrument. Some MS instruments can provide highly accurate molecular weight measurements and mass resolution allowing identification of unknown compounds based purely on MS data, thus making prior separation unnecessary. However, prior separation is essential for analyzing substances in most complex matrices – especially useful is the ultra-high performance LC (UHPLC). The advantages of using UHPLC rather than HPLC for the analysis of PPs in tea and wine were evaluated in one of the studies this thesis is based upon. The phenolic composition of red wine was also examined, using a novel LDI technique, following solid phase extraction (SPE). A class of small aromatic molecules (medicinally important alkaloids) also proved to be amenable to straightforward analysis, by thin layer chromatography (TLC) work-up followed by LDI-MS. Finally, a LC-MS method for monitoring neurotoxins (β-N-methyl-amino-L-alanine and 2,3-diaminobutyric acid) in complex biological matrices was developed and applied. Overall, the studies show that careful attention to the physicochemical properties of analytes can provide insights that can greatly facilitate the development of alternative methods to analyze them, e.g. by LDI. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: In press. Paper 5: Manuscript.</p>
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Återvinning av blandmaterial : Polyamid och PolyesterLjungholm, Hanna, Johansson, Amanda January 2015 (has links)
Om människor fortsätter med det konsumtionsbeteende som råder idag kommer jor-den resurser ta slut. Den fossila råvaran petroleum används vanligtvis vid framställ-ning av polyester och polyamid. Petroleum har en 100 000 årlig process, vilket är en ofantlig skillnad i förhållande till den takt som det förbrukas. Därför har eventuella möjligheter att återskapa en ny filament av återvunnet syntetiskt blandmaterial un-dersökts i detta arbete. Det finns befintliga metoder för att återvinna polyester och polyamid som homogena material. Dock vid återvinning i en gemensam process av materialen får den slutliga produkten en försämrad kvalité. Mekanisk och kemisk återvinning fungerar för att framställa syntetiska filament men i dagsläget kan endast den kemiska ge likvärdig kvalité på det återvunna filamentet i förhållande till den jungfruliga. Det har hittats ett flertal separationsmetoder som antas kunna tillämpas till bland-materialet. Olika egenskaper såsom densitet, polaritet och laddningsmöjligheter kan utnyttjas för att separera polymererna. Polyester och polyamid antas kunna separe-ras, dock görs inte detta på industriell basis troligtvis på grund av kvantitet, resurser och pris. / If people continue with the present consumption behaviour, the earth´s resources will run out. The fossil raw material petroleum is normally used in the manufacture of polyester and polyamide. Petroleum has a 100 000 annual process, which is a huge difference compared to the rate at which it is consumed. Therefore, any opportunities to recreate a new fibre from recycled synthetic bland materials are studied in this work. There are existing methods to recycle polyester and polyamide as homogeneous ma-terials. However, the recovery in a joint process get the final product a degraded quality. Mechanical and chemical recycling makes it possible to produce new syn-thetic filaments, but in the current situation, the chemical will provide comparable quality of the recycled filament in relation to the virgin. Several separation methods can be applied to the blend material. Various properties such as density, polarity and charging possibilities can be used to separate polymers. Polyester and polyamide are assumed to be separated, however, is not done on an industrial basis, probably because of the quantity, resources and money.
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Kostnadseffektivisering och kvalitetsförbättring gällande hantering av skärvätskaBrosgård, Philip, Fahlman, Anna January 2015 (has links)
Projektet bestod i att ge underlag för lämpliga och användbara lösningar för effektivisering av Kockums Maskins skärvätskehantering och kostnadsrelaterade faktorer gällande företagets skärvätska. En grundlig undersökning av lämpligt material inom projektets huvudsakliga område gjordes till en början för att därefter resultera i en vidare analys av företagets nuvarande system och hantering av skärvätskor. Utifrån denna analys påbörjades en vidare undersökning om möjliga förslag om förbättring gällande de berörda problemen. Genom direktkontakt med flertalet företag och personer inom hantering/inköp samt befintlig dokumentation gällande skärvätska, erhölls ett flertal lösningar och förbättringsförslag som senare utvärderades och användes vid framtagning av det sökta projektresultatet. Problematiken gällande valet av lösningar har att göra med det faktum att det krävs omfattande kompetens inom varje typ av lösningsgrupp för att uppfylla de krav och förhållanden som finns hos Kockums Maskin. Därmed har avgränsningar gjorts gällande direkta val av lösningar för att istället ge förslag på lämpliga lösningar gällande förbättring av kvalitet, som indirekt bör sänka den årliga kostnaden av skärvätska, utifrån Kockums Maskins egentliga behov. / The project was to provide the basis for appropriate and useful solutions for any eventually streamlining of Kockums Maskin's cutting fluid management. Cost-related factors regarding the company's cutting fluid are also included in this part. A detailed examination of suitable material within the project's main area were initially and subsequently result in a further analysis of the company's existing systems and management, regarding cutting fluids. Based on this analysis a further investigation on possible proposals was started for improvement regarding the issues involved with the solutions and the cutting fluids. Through direct contact with many companies and individuals in management/purchasing and existing documentation regarding cutting fluid, obtained a several solutions and suggestions for improvement regarding the searched area. This result was then later evaluated and used in the development of the project results. The problem regarding the choice of solutions has to do with the fact that it requires extensive expertise in every type of area to meet the requirements and conditions that Kockums Maskin demands. Thus, the boundaries claimed the election of solutions to instead provide suggestions for suitable solutions regarding the improvement of quality, which indirectly should lower the annual cost of cutting fluid, based on Kockums Maskin's actual needs.
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