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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Oxygenation conducted in low temperature clean water

Rosén, Elin, Abdelki, Andreas, Abdulla, Beyar, Bugurcu, Alan, El Nabelsi, Mahmoud January 2019 (has links)
Aeration tests were conducted under non-standard conditions with clean tap water in various temperatures below 20 °C, with the aim of studying changes that may occur. An initial deoxygenation of 0.8 litre water was performed with sodium sulfite and a cobalt catalyst pre-dissolved in water, in order to bind already present dissolved oxygen. The resulting dissolved oxygen concentration after 20 minutes did not decrease below 2 mg/L, despite increasing the sodium sulfite concentrations. Thereafter, a reoxygenation with the same time interval was conducted by using an aeration system, which resulted in an increase of saturated oxygen concentration with lower temperatures. pH-measurements were carried out during the whole experiment in order to follow the conversion of sulfite to sulfate. The pH-data obtained confirmed that sulfite had been converted to sulfate, although, a few deviations could be observed for most of the experiments. The conductivity was also measured to ensure that the sulfite had been properly dissolved when added to the water tank. In general, the conductivity never deviated and held a constant trend throughout the tests. The collected data could not be made of use in order to properly determine how the aeration, for temperatures below 20 °C, could be evaluated. Further tests have to be performed in order for a definite conclusion to be drawn.
112

Purification of photosystem II for future spectroscopic characterization

Lagerqvist, Henrik January 2019 (has links)
No description available.
113

Influence of pH on the size and shape of micellesformed by an amphiphilic drug in normal salinitystudied with static and dynamic light scattering

Östlund, Erik January 2019 (has links)
No description available.
114

Origin Identification of Pepper Spray and Tear Gas By Multivariate Data Analysis of Chemical Attribution Signatures

Jonsson, Sebastian January 2019 (has links)
No description available.
115

Synthesis of 2-(ethoxy(hydroxy)phosphoryl)-3-phenylpropyl ethanethioate

Eriksson, Tor January 2019 (has links)
No description available.
116

Purification and crystallisation of streptococcal collagen binding proteins

Bwanika, Harry Colyn January 2019 (has links)
No description available.
117

Emission of UV filter chemicals from PET fabric Examining the release to water during washing

Lindmark, Simone January 2019 (has links)
No description available.
118

Characterisation of NH3 adsorption on a V-SCR catalyst

Sjöberg, Elin January 2019 (has links)
All around the world the environmental focus is growing rapidly.The aim of thismaster’s thesis has been to work on developing experimental methodologies to achieve qualitatively, reliable and optimal data used on modelling. The selected study case is the analysis of ammonia adsorption on a V-SCR catalyst, which is an important step for future SCR-performance. Over the last years the mechanism of the V-SCR catalyst and the nature of its active sites have been widely discussed in order to be understood. However, so far, no clear conclusionshavebeen established about the catalytic mechanism, particularly on atomic level,thatdemonstrates the complexity of the catalytic chemistry within the SCR process. The kinetics of the adsorption of ammonia on a commercial V-SCR catalyst needs further investigation and much more knowledge is neededto understand the chemistry and the behavior behind it. In order to obtain this, new methods where high-quality data is achievedfor the adsorption phenomenon, need to be developed.The results from this workhas demonstrated the used method to be a reliable way to ensure reproductively dataat each temperature used for ammonia adsorption performed over a V-SCR catalyst. Further work with focus on the in-depth of the kinetics in the adsorptionprocessis needed.It is necessary toenhance the understanding ofthe behaviour of theadsorption on theactive sitesof the V-SCR catalyst surface as well as performing tests with lowerammoniaconcentrations for an even better understandingof the processes. / Över hela världen växerfokus på miljön snabbt. Insikten om behovet av att minska föroreningar och avgaser kräver nya lösningar inommånga områden. Syftet med examensarbetethar varit att utveckla experimentella metoder för att säkerställa att data som används vid modellering erhåller enbra kvalitet, är pålitlig och optimal. Det valda studiefallet har varit att analysera ammoniakadsorptionen på en V-SCR-katalysator, vilket är ett viktigt steg för SCR-prestandan.Under de senaste åren har mekanismen för V-SCR-katalysatorn och naturen av dess aktiva säten diskuterats i stor utsträckning för att bättre kunna förstås. Hittills har ingen klar slutsats etablerats om den katalytiska mekanismen, speciellt på atomnivå,vilket visar på komplexiteten iden katalytiska kemin inom SCR-processen. Kinetiken för adsorption av ammoniak på en kommersiell V-SCR-katalysator behöver undersökas ytterligare och mer kunskap behövs för att förstå kemin och beteendet bakom. För att uppnå detta måste nya metoder utvecklas där högkvalitativa data uppnåsfrån adsorptionen av ammoniaken på en V-SCR katalysator. Resultaten från detta arbete har visat att den valda metoden är ett tillförlitligt sätt att säkerställa reproduktivt datavid varje temperatur som används för den studerade adsorptionen av ammoniak på en V-SCR katalysator. Ytterligare arbete krävsmed störrefokus på djupet av kinetiken inomadsorptionsprocessen. Detta för att öka förståelsen för beteendet hosadsorptionen på de aktiva sätenahos ytan på V-SCR katalysatornsamt utförande av test med lägrekoncentration av ammoniak förenännu bättre förståelse.
119

Mineralogy of Lake Hotagen Sediments: Variations with Grain Size throughout Vertical Profile of a Sediment Core

Le Tran, Thai January 2019 (has links)
No description available.
120

Dynamics of a spin-forbidden reaction transforming methane to methanol / Dynamiken hos en spinnförbjuden reaction som förvandlar metan till metanol

Olsson, Susanna January 2019 (has links)
No description available.

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