Synthetic cannabinoids such as Δ8-Tetrahydrocannabinol (Δ8) are becoming increasingly popular. Δ8 was once studied for medicinal value and showed promise as an antiemetic. The typical synthesis of Δ8 includes a Cannabidiol (CBD) dissolved in a nonpolar solvent then reacted with a strong acid and washed in a basic solution to remove contaminants. We investigated the effects of varying the acid and solvent along with the washing method used in synthesizing Δ8 to produce novel synthetic cannabinoids and increase purity of Δ8. CBD was reacted with p-Toluenesulfonic acid monohydrate or Phosphotungstic acid dissolved in Toluene, Cyclohexene, or Cyclohexane. Samples were either washed with sodium bicarbonate or extracted from the non-polar layer when added to a biphasic solution of cyclohexane and either acetonitrile or ethanol. Samples were taken at 1-, 24-, 72-, 96-, 168-, and 288-hour increments. Samples were diluted with DCM and analyzed via GCMS. Notable cannabinoids synthesized include CBC, CBN, isomers of CBD, and unknown hydrated cannabinoids. Through comparative GCMS analysis cyclohexane was discovered to be the commercial solvent of choice. Residual cyclohexane (<4%) was identified in all similar samples and poses unknown toxicity. The biphasic extraction and wash produced samples with greater purity while also reducing byproduct contamination when compared to commercial samples. This work will be useful in identifying cannabinoid byproducts in the production of Δ8 from which future drugs may be developed. This work will also be key in highlighting hidden toxic compounds related to of unregulated synthetic cannabinoid production.

Consumers place a high level of importance on flavour when assessing the acceptability of food. The flavour of dairy products can be affected by heating both during processing and by consumers during food preparation. Of particular importance to the flavour of heated dairy products is the highly complex network of Maillard reactions. Previously, emphasis has been placed on undesirable flavours generated through the Maillard reaction in dairy products and efforts have been made to minimise the formation of these flavours. However, beneficial flavours are also formed by the Maillard reaction. Dairy products such as ghee are formed by heating and are characterised by their unique flavours; these flavours are generated by the Maillard reaction. The objective of this thesis was to unravel the factors that influence the Maillard and caramelisation reactions that occur during the cooking of ghee. Particular focus was placed on the impact that the structure of the cream had on the reaction, and how manipulation of these parameters could provide an avenue for the control of the Maillard reaction. The development and validation of model reaction systems for the Maillard and caramelisation reactions involved the variation of parameters including cooking time, temperature, pH, phosphate buffers and salt. A group of eleven compounds including acetic acid, furfural, 2-acetylfuran, butyrolactone, 2(5H)-furanone, furfuryl alcohol, maltol, 2- acetylpyrrole, hydroxymaltol, hydroxymethylfurfural (HMF) and dihydro-4-hydroxy-2(3H)- furanone (DHHF) were monitored to determine the impact of these parameter changes. These results provided a starting point to assess the impact of food structure on these reactions. To assess the impact of food structure a series of matrix structures were designed starting from an aqueous matrix. The first component that was added to the aqueous matrix was fat to generate a two phase structure. Emulsion structures were then formed from the two phase structure using emulsifiers and high pressure homogenisation. Analysis of the volatile compounds formed as the matrix structures were altered was carried out using headspace solid phase microextraction/ gas chromatography mass spectrometry (SPME/GCMS). Results indicated that fat is a key structural component in flavour generation via the Maillard reaction. This could have implications for low fat foods where the flavour developed during cooking is important. The addition of fat indicated a significant impact on the Maillard reaction with a less significant impact seen on the caramelisation reaction. The formation of two emulsions with inverted structures provided a means to alter the ratio of volatile compounds in the cooked samples. The oil in water emulsion generated a volatile compound profile similar to that of the fat containing matrix, whereas the water in oil emulsion produced a different ratio of these same compounds. The results reported in this thesis shed some light on the relationship between food structure and flavour formation during the cooking of milk fat emulsions. These structures will create future opportunities to manipulate the structure of food to control flavour formation.

The ultimate goal of this research is to provide a low cost, efficient, reproducible, quantitative, non-invasive screening method to diagnose diseases at an early stage through identification of volatile biomarkers of disease. Progress has been made in the areas towards development of an analytical system that can provide a rapid and specific assay for above mentioned Volatile Organic Compounds (VOCs). (i) Methods have been designed for the collection, concentration, identification and quantification of volatile biomarkers. (ii) Advanced signal processing evaluation of data has tentatively identified key VOCs patterns with breath and body odor. (iii) Novel absorbent coatings have been studied for use with miniature chemical sensors that one day may be part of a portable analytical system. Both breath and body odor contain a complex mixture of chemicals, which are influenced by many internal and external factors. Breath and skin odor samples were collected with minimum external contaminations using traditional SPME and active SPME GCMS techniques. Body odor from 65 human subjects was tested with and without selected scent removal products. Breath samples were collected from 21 canine subjects. The VOCs profiles of these samples were determined and then statistically treated with principal component analysis, discriminant analysis, and tree regression techniques to simplify and interpret the complex mixtures. While much of our work has utilized large bench-top equipment, our over-arching goal is to provide a portable device that can diagnose diseases at an early stage. Concurrent work was done to enhance the performance of a miniaturized detector for the detection of potential biomarkers. Two organic polymers mixed with conductive carbon nanoparticles were deposited between the microcapacitor plates of microsensors using ink-jet technology. Microsensors were also fabricated using conducting ionic liquids. The performances of the individual chemicapacitive sensors were characterized through exposure to different concentrations of varied volatile organic compounds with different functional groups in a climate-controlled vapor delivery system.

Although quality of commercial fish oil is of the upmost importance to both suppliers and consumers, it can be difficult to maintain due to rapid lipid oxidation attributable to the high levels of EPA and DHA. Fish oil quality can be assessed in a number of ways; this paper focuses on ethyl ester (EE) content and oxidation products. Fish oil supplements are sold as both triacylglycerols (TAG) and EE. TAG products are more resistant to oxidation, have better bioavailability and are generally considered to be of higher quality. Here, a method is described to quantify EE in fish oil using solid phase microextraction (SPME) headspace analysis and gas chromatography-mass spectrometry (GCMS). A related aspect of quality is state of oxidation and although the causes of oxidation in fish oil are well known, there is little research on the kinetics of the oxidation process. The work presented here monitors hydroperoxides to model the kinetics of oxidation in two commercially available fish oil supplements by fitting the data to the Arrhenius model. It was determined that the same mechanisms of oxidation hold at temperatures ? 40 °C and thus, this temperature was used in the final stages of this work where accelerated stability testing of fish oil was conducted. Currently, taste panels are the only reliable method to assess the sensory properties of fish oil, but these are costly and subjective. Described here is an alternative method using SPME-GCMS to monitor volatile oxidation products. Two different statistical methods were used to identify oxidative volatiles that correlate with sensory characteristics of fish oil. First, stepwise discriminant function analysis (DFA) was used to identify volatiles that could be used to classify oil as acceptable or unacceptable based on sensory analysis. Principal component analysis (PCA) and linear regression were then applied with greater success. Both techniques identified similar oxidative volatiles as being important to sensory properties. It is anticipated that these methods could be adopted by fish oil manufacturers as measures of quality.

<p>This paper deals with the connection between food and burial habits during the late Iron Age in present-day Sweden. The archaeological material used in the study consists of 16 potsherds from a burial site at Alsike hage, Alsike parish, in the province of Uppland in east-central Sweden. On these potsherds have been conducted FTIR- and GCMS-analyses, in order to see what types of food have been deposited in the burials. Furthermore, the result of the GCMS-analyses has been compared to contemporary material from both burial sites and settlement sites, in order to establish whether differences between the compared materials exist. The analyses show that there are differences between the material from burial sites compared with the material from settlement sites, but not any particular differences between the material from different burial sites. Among these differences we can see that the settlement sites show: a higher amount of total lipid content, a higher amount of vessels which contained lipids indicating that food was heated in them, a higher amount of vessels which contained lipids from crop products as the only content, and a higher amount of vessels which contained lipids from ruminant animals. The interpretation of these results is also discussed in the paper. Furthermore, the results of the FTIR-analyses also shows a good correlation with the results from the GCMS-analyses, it seems that the organic “foodcrusts” analysed with FTIR indeed stem from the same meal indicated by the GCMS-analyses.</p>

This paper deals with the connection between food and burial habits during the late Iron Age in present-day Sweden. The archaeological material used in the study consists of 16 potsherds from a burial site at Alsike hage, Alsike parish, in the province of Uppland in east-central Sweden. On these potsherds have been conducted FTIR- and GCMS-analyses, in order to see what types of food have been deposited in the burials. Furthermore, the result of the GCMS-analyses has been compared to contemporary material from both burial sites and settlement sites, in order to establish whether differences between the compared materials exist. The analyses show that there are differences between the material from burial sites compared with the material from settlement sites, but not any particular differences between the material from different burial sites. Among these differences we can see that the settlement sites show: a higher amount of total lipid content, a higher amount of vessels which contained lipids indicating that food was heated in them, a higher amount of vessels which contained lipids from crop products as the only content, and a higher amount of vessels which contained lipids from ruminant animals. The interpretation of these results is also discussed in the paper. Furthermore, the results of the FTIR-analyses also shows a good correlation with the results from the GCMS-analyses, it seems that the organic “foodcrusts” analysed with FTIR indeed stem from the same meal indicated by the GCMS-analyses.

Climate change and land use transition are the main drivers of watershed hydrological processes. The main objective of this study was to assess the hydrometeorological responses to climate and land use changes in the Jhelum River Basin (JRB), Pakistan. The development of proper climate information is a challenging task. To date, Global Climate Models (GCMs) are used for climate projections. However, these models have a coarse spatial resolution, which is not suitable for regional/local impact studies such as water resources management in the JRB. Therefore, different downscaling methods and techniques have been developed as means of bridging the gap between the coarse resolution global models projection and the spatial resolution required for hydrological impact studies. Statistical Downscaling Model (SDSM) and Long Ashton Research Station Weather Generator (LARS-WG) are selected in this study for downscaling of temperature and precipitation. Both downscaling approaches consider three climate models and two emission scenarios (i.e., RCP4.5 and RCP8.5) in order to sample the widest range of uncertainties in climate projections. Current land use and land cover (LULC) maps are generated from Landsat imagery to analyze the pattern and dynamic of land use change. Both climate projections and LULC are fed into SWAT (Soil and Water Assessment Tool) hydrological model to investigate the streamflow dynamics. The results indicate good applicability of SDSM and LARS-WG for downscaling of temperature and precipitation in three future periods (2020s, 2050s and 2080s). Both models show an increase mean annual max temperature, min temperature and precipitation as 0.4-4.2°C, 0.3-4.2°C and 4.4-32.2% under both RCPs scenarios. Similarly, results of SWAT model suggest an increase in mean annual discharge about 3.6 to 28.8% under RCP4.5 and RCP8.5. The study also revealed that water yield and evapotranspiration in the eastern part of the basin (sub-basins at high elevation) would be most affected by climate change. The results of LULC change detection show that forest exhibited maximum positive change while agriculture showed maximum negative change during 2001-2018. SWAT model simulations suggested that implementation of afforestation in the watershed would reduce surface runoff and water yield while enhancing the evapotranspiration. It is recommended that authorities should pay attention to both climate change and land use transition for proper water resources management.

En nyligen genomförd studie visade att reaktioner mellan vissa radikaler och omättade alkener är snabbare vid rumstemperatur än vad man tidigare har trott. Dessa reaktioner är viktiga för atmosfäriska oxidationscykler och följaktligen var syftet med detta masterprojekt att beräkna hastighetskonstanterna för dessa reaktioner mellan metyljodid och 1-jodidpentan med tetrametyletylen, isopren och limonen vid rumstemperatur genom att kvantifiera respektive epoxid; tetrametyloxiran, isoprenmonoxid och limonen 1,2 epoxid, som producerades. För att uppfylla syftet utfördes experiment på referensföreningarna tetrametyletylen, isoprenmonoxid, limonen och limonen 1,2 epoxid och på prover tagna från en kolonnflödesreaktor. Dessa experiment genomfördes för att kunna utveckla en lämplig provtagningsmetod och analysmetod med termisk desorptionsenhet samt gaskromatografi och masspektrometri (TD-GCMS). Slutsatsen som drogs var att Tenax® TA adsorbentrör är kompatibla med dessa ämnen och att den föreslagna TD-GCMS metoden är effektiv. Dessutom drogs slutsatsen att tetrametyloxiran inte hittades i reaktorproverna (varken i alkenproverna eller reaktorproverna), vilket resulterade i att hastighetskonstanten inte kunde beräknas. Dessutom var kvantifiering av reaktorproverna inte möjlig. / A recent study has shown that the reaction between some radicals and unsaturated alkenes is faster at room temperature than previously believed. These reactions are important for atmospheric oxidation cycles and therefore the purpose of this master project was to measure the rate coefficients for the reactions between methyl iodine and 1-iodopentane with tetramethylethylene, isoprene and limonene at room temperature by quantifying the respective epoxide; tetramethyloxirane, isoprene monoxide and limonene 1,2 epoxide, produced. In order to fulfill the purpose, experiments were conducted using the reference compounds of tetramethylethylene, isoprene monoxide, limonene and limonene 1,2 epoxide and on column flow reactor samples produced in the above mentioned reactions. These were performed in order to be able to develop an appropriate sampling method, and analysis method using thermal desorption unit gas chromatography and mass spectrometry (TD-GCMS). It was concluded that Tenax® TA adsorbent tubes are compatible with these substances and that the TD-GCMS method suggested is appropriate. It was also concluded that no tetramethyloxirane was found in the reactor samples (neither in alkene samples nor after the reactions), resulting in that it was not possible to calculate the rate coefficient. Moreover, the quantification of the reactor samples was not possible.

An apple wine produced by Kiviks Musteri AB have an undesirable flavor of yeast. As a step in the development to reduce this off-flavour the wine flavor was analyzed by gas chromatography-mass spectrometry (GCMS) with headspace solid-phase microextraction (HS-SPME). Two other wines without the flavor of yeast where analyzed as references. Samples from the production step prior to clarification where also analyzed. Through matching against mass spectrum library, retention index and in some cases references a total of 37 volatile compounds were identified in the apple wines. Some uncertainty in the relative quantification of a few compounds was caused by insufficient clearance (deadsorption) of the SPME-fiber. When comparing the different wines the compounds were divided into groups: key compounds, ethyl esters, derivatives of 3-methyl-1-butanol, other compounds: group 1 and other compounds: group 2. In each group the percent area for each compound was calculated. Comparing the percent area of each wine showed that the samples prior to clarification contains a higher number of volatile compounds e.g. ethyl esters and 3-methylbutanol derivatives than the final wine products. The comparisons also revealed differences between the wines. The results from the analyses indicated that the compounds that hypothetically contribute to the yeast-flavor could be 2-phenylethanol; 3-methylbutanoic acid; 2-methyl-1-butanol; 2-phenylacetaldehyde och 2-methylthiolan-3-one. The results need to be verified e.g. by an odor panel if they are going to be useful for Kivik Musteri AB in its effort to solve the taste problem in the wine.

<p>This project was aimed to study the degradation of polystyrene-butadiene-styrene block copolymer (SBS). SBS is used to modify bitumen, the binder in asphalt. From earlier studies it is known that SBS degrades in bitumen, but the degradation products have not been identified. To be able to determine the long term effects of SBS in the environment, degradation products need to be identified. Polystyrene forms rigid blocks with polybutadiene as a rubbery matrix between the ridgid blocks. When blended in bitumen, the polystyrene blocks are crosslinked to form a three dimensional network. SBS is an elastomer and has the ability to regain its shape after being a subject of mechanical force. According to the pre references the polymers had to be degraded in similar ways as they would in bitumen. Since bitumen is a very complex matrix with high boiling point and viscosity, there would be difficulties separating polymers from the bitumen. We made an assumption that it would be plausible for the degradation products formed in bitumen to form even with no bitumen present. Four different SBS polymers were used. One of the polymers was branched. Another had a high content of 1-2 polybutadiene. The third was a diblock copolymer (SB) with low styrene content compared to the others. The last was a linear SBS. The polymers were degraded in pieces of apparatus used for study ageing characteristics of bitumen as well as they were aged by refluxing in hexane. The degradation products were extracted by Solid Phase Extraction (SPE) and identified by GC-MS. Due to instrumental limits there were not many degradation products identified. The main products detected included saturated hydrocarbons in the range of 16-31 carbon atoms as well as squalene.</p> / <p>I det här projektet studerades nedbrytning av styren-butadien-styren block kopolymerer (SBS). SBS används för att modifiera bitumen vars användningsområde är som bindemedel i asfalt. Tidigare studier har visat att SBS bryts ned i bitumen, men nedbrytningsprodukterna har inte identfierats. För att kunna avgöra vad SBS har för långsiktiga effekter på miljön måste nedbrytnignsprodukterna identifieras. I SBS bildar polystyren styva block medan polybutadien fungerar som flexibla bryggor mellan polystyrenblocken. När SBS blandas med bitumen korslänkas polystyrenblocken så att ett tredimensionellt nätverk bildas. Eftersom SBS är en elastomer har den förmågan att återfå sin ursprungliga form efter att ha blivit utsatt för mekanisk stress. Enligt de givna förutsättningarna för studien skulle polymererna brytas ned på samma sätt som om de skulle ha varit lösta i bitumen. Eftersom bitumen är en komplex matris med hög kokpunkt och viskositet skulle det varit svårt att separera polymererna och deras nedbrytningsprodukter från bitumenet. Vi gjorde ett antagande om att det förmodligen bildas samma nedbrytningsprodukter som om bitumen varit närvarande även om nedbrytningen sker utan bitumen närvarande. Fyra olika SBS polymerer användes. En av polymererna var grenad. En annan hade en stor andel 1,2-polybutadien. Den tredje var en diblock kopolymer (SB) med lågt styren innehåll jämfört med de andra. Den sista polymeren var linjär. Polymererna åldrades i apparatur framtagen för att studera åldring av bitumen. Polymererna åldrades även genom att återloppskokas i hexan. Nedbrytningsprodukterna extraherades via fastfasextraktion (SPE) och identifierades med GC-MS. Genom instrumentella begränsningar kunde bara ett fåtal nedbrytningsprodukter identifieras. Bland de produkter som identifierades fanns alkaner och alkener med mellan 16 och 31 kolatomer, men även skvalen identifierades som nedbrytningsprodukt. Lågmolekylära ämnen kan ha ventilerats bort för att vi inte hade tillgång till apparatur för adsorbtion av flyktiga ämnen för injektion i GC-MS. </p>