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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.
121

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.
122

The Influence of Synthesis Conditions on the Formation of the Prussian Blue Analogue Cu[Fe(CN)6]2/3 ∙ nH2O

Stolpe, Amanda January 2019 (has links)
No description available.
123

Method for quantification of Ca, Cu, Fe, Mg, Sr and Zn in low concentrated whole blood samples using ICP-AES

Mortensen, Magnus January 2019 (has links)
No description available.
124

Electrode modification based on electrochemical grafting with p-carboxybenzene diazonium couple with an in situ deposition of bismuth for detection of lead and cadmium using square wave anodic stripping voltammetry

Nguyen, Thi Ngoc Huyen January 2019 (has links)
No description available.
125

Development of Indole-Based Inhibitors of Acetylcholinesterase to Combat Mosquito-Borne Diseases

Stangner, Konstanze January 2019 (has links)
No description available.
126

Chemical characterization of phenols and taste-activesubstances in wine using liquid chromatography - massspectrometry

Johansson, Erika January 2018 (has links)
Wine characterization of taste and odor of a wine is important to keep up with consumersinterest and ensure quality of wine. In Sweden, wine is sent for destruction every year and oneof the reasons is that some wines have a deviant taste and odor profiles than described on thelabel. The aim for this project was to perform a chemical analysis of wine to identify differenttaste-active compounds to connect to different taste sensations such as sweetness, acidity,bitterness and the mouthfeel of astringency. Wine profile patterns were also created todistinguish between the composition of these compounds in sixteen different wines of differentcolors. The targeted compounds were fifteen compounds which included phenolic compounds,amino acids and organic acids. The analysis were performed by liquid chromatography massspectrometry. A literature survey was performed for selection of an appropriate method for theanalysis of the targeted compounds. Fourteen out of fifteen compounds were detected in thewine samples. Fifteen out of sixteen wines contained tartaric acid, while proline was found inall wines and vanillin only in one sparkling wine. The red wines showed higher concentrationsin compounds connected to bitterness and astringency and sparkling wine contained higheramounts of the compounds connected to sweet and sour taste. The wine profile patterns werecompared to see both similarities and differences within the same color wines.
127

Analysis of odourant compounds in wine : - With headspace solid-phase microextraction and gas chromatography- mass spectrometry

Ödmar, Emma January 2018 (has links)
Wine is a drink that can enhance the flavour experience of food, which is why it is important that the wine’s sensory profile is explained correctly to the consumers. In this study, headspace solid-phase microextraction gas chromatography mass spectrometry was used to characterise odourant compounds in wine to find chemical markers to explain wine sensory profiles instead of sensory analysis. The study included 16 different wines, red, white, orange and sparkling, where the nine most abundant peaks in each wine sample were evaluated. Homologue patterns based on areas were used to compare profiles between different wines. When studying homologue patterns for each wine and comparing within wine groups, differences and similarities can be seen. All wine samples contained isoamyl alcohol and the majority of them also contained ethyl decanoate, octanoic acid and decanoic acid. Six out of eight red wines contained ethyl succinate and five of them also contained ethyl hexanoate. All white wine samples showed presence of ethyl octanoate and ethyl hexanoate. The orange wines also contained ethyl octanoate and ethyl hexanoate, along with pentanoic acid. Both sparkling wines contained ethyl octanoate and ethyl hexanoate in addition with phenylethyl alcohol. However, a more thorough study covering more compounds to identify the less obvious differences of wine would have to be performed for a more precise explanation of the wine’s characterisation and sensory profile. It should be noted that the method of this study does leave room for improvements to improve the quality of the results. For example, since the most abundant compounds are not necessarily the ones with the most powerful odours, quantification based on response of an internal standard would strengthen the study. Additional compounds in the samples could also be further investigated. Statistically the method would also need improvement for satisfactory results regarding reproducibility of the samples.
128

Suspect screening of human serum with UHPLC-QTOF/MS

Poolsri, Louise P. January 2018 (has links)
The number of environmental pollutants has increased due to the increased production and the use of various chemicals in different applications. An estimation of today’s synthetic chemicals is approximately 50,000 to 100,000 and many of them may be harmful to humans and the environment. Persistent Organic Pollutants (POPs) are a specific type of environmental pollutants that are very stable and do not decompose easily. Example of those are pesticides, phthalates, phenols and per-/polyfluorinated alkyl substances (PFASs). Several studies have reported that environmental pollutants may particularly affect pregnant women and the fetus. The aim of the present study was to characterize the environmental pollutant profile in serum extracts of pregnant women, by analyzing the blood and characterizing the chemicals using a suspect screening approach with chromatography combined with high-resolution mass spectrometry. The samples in this study were extracted with solid-phase extraction (SPE) prior to the instrumental analysis, to precipitate the proteins as well as to remove some phospholipids and other contaminants that could interfere with the instrumental analysis. Quality control samples was used to validate the instrumental performance. Twelve compounds out of the 38 suspects were identified with this method, including both fatty acids and a few environmental pollutants. The detection rate of the fatty acids was higher than the environmental pollutants, which are; perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), monooctyl phthalate and 3,5-ditertbutyl salicylic acid. The low detection rate of the environmental pollutants, particularly of PFASs could be due to the low sensitivity of the method for the PFASs but also due to the decreased exposure to those compounds, since the samples were collected between 2013 to 2016, after the restrictions in the use of the two most common PFASs; PFOA and PFOS.
129

Kan läroböcker i kemi för åk 7-9 leda till missuppfattningar? : En analys av ämnesområdena växthuseffekt, ozonlager samt fotosyntes och respiration i fem läroböcker i kemi.

Wettergren, Leila January 2016 (has links)
No description available.
130

Charge Transport Simulations for Organic Electronics : A Kinetic Monte Carlo Approach

Volpi, Riccardo January 2015 (has links)
In this thesis we focus on the modelling and simulation of organic electronic devices, investigating their structural and electronic properties. Organic devices have attracted great interest for their innovative properties, but their functioning still represent a theoretical and technological challenge. They are composed by one or more organic materials depending on the particular application. The morphology of organic devices in the single phase or at the interface is known to strongly determine mobility and efficiency of the devices. The structural disorder is studied through molecular dynamics (MD) simulations. Marcus formula is used to calculate the hopping rate of the charge carriers and the model developed is tested by simulations in a Kinetic Monte Carlo scheme. The dependence of the transfer integrals on the relative molecular orientation is achieved through a weighted Mulliken formula or through a dimer projection approach using the semi-empirical Hartree Fock method ZINDO. Electrostatic effects, have been included through atomic charges and atomic polarizabilities, calculated at the B3LYP level of theory. The inclusion of electrostatic effects has been shown (through simulations in 4PV and C60) to be crucial to obtain a good qualitative agreement with experiments, for both mobility field and temperature dependence in the single phase. In particular the external reorganization energy, calculated through the polarization of the environment, has been shown to have a great impact on the conduction, shifting the inverse Marcus region and helping CT state separation at the interface (between C60 and anthracene).

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