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The aim of this project was to compare two methods for the extraction of perfluoroalkyl substances (PFASs) in water samples. The methods compared were solid phase extraction (SPE) and supramolecular solvents (SUPRAS). Solid phase extraction is a sample preparation process where the desired compound passes through a solid phase and the method uses the affinity for the compound of interest to retain it in the solid phase while the undesired compounds pass through. Supramolecular solvents are an alternative approach for extraction of contaminants, for example PFASs. Supramolecular solvents are liquids that generates from compounds known as amphiphiles. The desired compound is extracted by binding with ionic bond, hydrogen bond, dipole-dipole bond, or other depending on the desired compound. A comparison of methods was evaluated based on method detection limits (MDL), recovery, matrix effects and repeatability. The recoveries for SPE (n=11) were best for short-chain PFASs with recoveries between 81-128%. The recoveries decreased with increasing carbon chain length, probably due to the sorption of analytes to the wall of the container or the reservoir that were not washed thoroughly. The matrix (e.g. surface water) for the solid phase extracted samples were concluded to slightly suppress the signal of most PFASs. The repeatability for the SPE samples had values between 8-59%, with an average of 18%. The recoveries of PFASs (n=4) when using SUPRAS for the extraction of PFASs from water samples were generally lower than those of the SPE method. Especially the short-chain PFASs have poor recoveries in SUPRAS extraction. For longer carbon chain PFASs the recovery for the samples extracted with SUPRAS showed better values (58-135%) but with decreasing chain length the recoveries also decreased. For SUPRAS method to be a feasible option, extraction efficiency of 50-120% would be needed. The matrix effects indicated that the matrix of the SUPRAS extracted samples enhanced the signal of most PFASs. The repeatability could not be calculated for the environmental (SUPRAS Method 1) SUPRAS samples since no replicate blanks were extracted. Spiking experiments on Milli-Q water was performed and had RSD values between 22-85% with a mean value of 39 %. This preliminary test of using SUPRAS as extraction method of PFASs in water need to be further developed. At present SUPRAS is not as efficient for the extraction of PFASs from water as using solid phase extraction. Screening of solvents and possibly salting out need to be tested to increase the efficiency of the extracted compounds.

Analytical chemical information is needed in all areas of human activity including health care, pharmacology, food control and environmental chemistry. Today one of the main challenges in analytical chemistry is the development of methods to perform accurate and sensitive rapid analysis and monitoring of analytes in ‘real’ samples. Electrochemical biosensors are ideally suited for these applications. Despite the wide application of electrochemical biosensors, they have some limitations. Thus, there is a demand on improvement of biosensor performance together with a necessity of simplification required for their mass production. In this thesis the work is focused on the development of electrochemical sensors with improved performance applicable for mass production, e.g. by screen printing. Biosensors using immobilized oxidases as the bio-recognition element are among the most widely used electrochemical devices. Electrical communication between redox enzymes and electrodes can be established by using natural or synthetic electron carriers as mediators. However, sensors based on soluble electronshuttling redox couples have low operational stability due to the leakage of water-soluble mediators to the solution. We have found a new hydrophobic mediator for oxidases – unsubstituted phenothiazine. Phenothiazine and glucose oxidase, lactate oxidase or cholesterol oxidase were successfully co-immobilized in a sol-gel membrane on a screen-printed electrode to construct glucose, lactate and cholesterol biosensors, respectively. All elaborated biosensors with phenothiazine as a mediator exhibited long-term operational stability. A kinetic study of the mediator has shown that phenothiazine is able to function as an efficient mediator in oxidase-based biosensors. To improve sensitivity of the biosensors and simplify their production we have developed a simple approach for production of graphite microelectrode arrays. Arrays of microband electrodes were produced by screen printing followed by scissor cutting, which enabled the realization of microband arrays at the cut edge. The analytical performance of the system is illustrated by the detection of ascorbic acid through direct oxidation and by detection of glucose using a phenothiazine mediated glucose biosensor. Both systems showed enhanced sensitivity due to improved mass transport. Moreover, the developed approach can be adapted to automated electrode recovery. Finally, two enzyme-based electrocatalytic systems with oxidation and reduction responses, respectively, have been combined into a fuel cell generating a current as an analytical output (a so-called self-powered biosensor). This was possible as a result of the development of the phenothiazine mediated enzyme electrodes, which enabled the  construction of a cholesterol biosensor with self-powered configuration. The biosensor generates a current when analyte (cholesterol) is added to the cell. The biosensor has been applied for whole plasma analysis. All developed concepts in the thesis are compatible with a wide range of applications and some of them may even be possible to realize in a fully integrated biosensor unit based on printed electronics.

This thesis is a short review of six papers (Papers 1-6,page 5) concerning studies of enamines from 2-indanones. The unusuallystable 2-(N-pyrrolidyl)indene has been studied (Paper 2 ). As a base catalyst this enamine rearranges 1-methylindene to 3-methylindene with a lower rate constant compared with triethylamine. During this 1 ,3-prototropic rearrangement no hydrogen exchangewas observed (Paper 1). Special attention has been drawn to 1 ,3-rearrangements ofalkyl-substituted enamines of 2-indanone. Prom 1-methyl-2-indanone, which was most conveniently prepared by oxidation of the correspondingindene, a series of enamines has been prepared with varyingamine components. A study of the kinetic control of the formation of these enamines showed that the less substituted double-bondisomer was formed more rapidly than the other form. Furthermore, the nature of the amine group has a significant influence on the composition of the equilibrium mixture observed, but the isomericratios obtained were unexpected in the light of earlier investigationsof enamines from 2-methylcyclohexanone (Paper l). A 13C NMR study of these 2-cycloaminoindenes showed that introduction of a 1-methyl substituent caused a decrease in overlap but the magnitude of this perturbation was almost independent of the variation of the amine component. Furthermore, when using pyrrolidineor hexamethyleneimine as amine parts this decrease in overlapwas of a comparable magnitude with the diminished conjugationnoted in the 3-methyl isomers. However, when piperidine or morpholinewas used the decreased delocalization was more pronounced inthe 3-methyl tautomers compared with the 1-methyl analogues (Paper6). One isomer, 1-methyl-2-(N-piperidyl)indene, has been shown toundergo base- as well as acid-catalyzed 1,3-tautomerizations inpyridine solvent. The isomerization rates using 1,4-diazabicyclo-(2.2.2.)octane or quinuclidine as base catalysts were considerably slower than the rate of the acid-catalyzed reaction or the basecatalyzedrearrangement rates involving alkyl-substituted indenesas substrates. This retarding effect, caused by the amine group, is in agreement with differences in pKA values obtained via simpleHückel calculation (Paper 4). The reaction between pyrrolidine and 1-(2-indanylidene)indan--2-one has been investigated. Two possible mechanisms were sugges-ted for the formation of products consisting of a linear dienamineand an indenyl-substituted enamine (9:1). In the main productisolated by recrystallization, the indenyl substituent was shownto be twisted out of conjugation. This dienamine also underwentacid-catalyzed isomerization to form the enamine product (Paper 3). Convenient syntheses of the pharmacologically interestingN-substituted 2-aminoindanes have also been described. The perchloratesalts of the enamines were treated with sodium borohydride in methanol to afford the desired products (Paper 5). / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1974</p> / digitalisering@umu

This thesis is devoted to the development of new organophosphorus compounds for potential uses in material science and as reagents in Organic Chemistry. Organophosphorus compounds in a single molecule or organic electronics context are appealing as the phosphorous centers perturb the electronic properties of the π-conjugated systems while at the same time provide synthetic handles for subsequent synthetic modifications. As such, new synthetic methodology to such compounds and the exploration of new building blocks is of considerable interest. In a different study, novel organophosphorus compounds are synthesized and shown to promote a reaction in Organic Chemistry that has previously not been possible, i.e. the stereoselective reductive coupling of aldehydes to alkenes. Such developments enlarge the toolkit of reactions that are available to Organic Chemists, and may impact the synthetic routes to pharmaceuticals and other important commodity chemicals. A general introduction of the key structural unit of this thesis, phosphaalkenes, is given in the first chapter. The synthesis, reactivity, properties and applications of these P=C double bond containing compounds are highlighted. The Wittig reaction and its variations as well as the phosphorus analogues that produce phosphaalkenes are outlined in detail. The second chapter is dedicated to the synthesis of a precursor that is used for the preparation of novel π-conjugated, organophosphorus compounds. C,C-Dibromophosphaalkenes are prepared and the halide substituents are used for the selective introduction of acetylene units. Besides the phosphaalkenes, the successful syntheses of two new diphosphenes is presented, indicating a broad applicability of the precursors. The third chapter is dedicated to the isolation of a metal-free phosphanylphosphonate that transforms aldehydes quantitatively to their corresponding E-phosphaalkenes in a transition metal-free phospha-HWE (Horner-Wadsworth-Emmons) reaction. The reaction benefits from mild conditions, high E-stereoselectivity, and a broad substrate scope. In the last chapter, a novel method for the reductive coupling of aldehydes to olefins is introduced. The reaction, which is a vast improvement over the McMurry coupling, allows for the selective synthesis of symmetrical and most importantly unsymmetrical E-alkenes. The phosphanylphosphonate mentioned above is the reagent that facilitates the coupling of the aldehydes via a phosphaalkene intermediate. This one-pot reaction benefits from mild conditions, good conversions, and high E-stereoselectivity. In summary, the thesis presents novel aspects of organophosphorus chemistry. These include the preparations and exploration of interesting precursors for the construction of π-conjugated organophosphorus compounds, and the use of organophosphorus reagents for unprecedented transformations in Organic Chemistry.

The analytical method of X-Ray Fluorescence has come into quick usage lately with the recent development of hand-held devices that can be taken anywhere. The method can be utilized for quantitative and qualitative analysis of the sample in question. Both methods su er from potential sources of errors that can decrease the accuracy and reliability of the acquired data. This thesis aim to describe the theoretical foundations of some of these issues that can occur in analysis, explaining why the readings from X-Ray Fluorescence (XRF) can di er greatly from the actual value unless proper precautions are taken.

In a cement plant, as in any industry, there are regulations of the level of emissions. One way to reduce the emissions is by decreasing the clinker content in the produced cement by addition of remains from other processes that together with lime produce the same products as pure clinker. The produced clinker varies in reactivity and in a more reactive clinker the addition could be increased, reducing the emissions per tonnage of cement. Today the produced cement is analyzed for strength and the results are then evaluated, which is about 1.5 months after the clinker was produced. Clinker samples from the kiln are analyzed every third hour with X-Ray diffraction to see that the composition is correct. If those samples could be used to predict the strength or heat evolution, parameters could be changed directly to keep a stable clinker production. This would give a more stable product and require less energy to produce, thereby producing less emission. In this study, Florida clinker samples have been mixed with 3.96 % gypsum and ground in a 5kg-mill. The ground cement has been analyzed for sulfur, loss of ignition, free lime, compressive strength and setting time. They have also been analyzed with X-Ray fluorescence, calorimetry and X-Ray diffraction. The results have been correlated with each other two by two to see if any connections could be found. The results of the correlation analysis showed 9 good correlations. No correlation was found between any clinker mineral or module to heat evolution, compressive strength or setting time. Multivariate analysis has also been used but more data is needed for it to be able to predict the cement strength. The calorimetric analyses were performed while developing a method. The method seemed robust and small changes had no large significance although the mixing time could rather be too long since shorter mixing time was not enough.

People tend to spend more and more time indoors, constantly breathing indoor air. In indoor air there is a mixture of chemicals from both the outdoor air, which is let in through the ventilation systems, and from the materials and products that are used indoors. To maintain good health, good indoor air quality (IAQ) is essential, not only at home but also at work. Some workplaces are more prone to air contamination than others, beauty salons being a great example. This is simply because a large number of products are used, all with a complex composition of different substances. In this study, the concentrations of volatile organic compounds (VOCs) and aldehydes are measured in the air of different types of beauty salons and a gym. Three different types of beauty salons are included; one hair salon using traditional hair products, one hair salon using organic products and the third salon is a nail salon. The gym is included as a reference facility where low emissions of VOCs and aldehydes are expected. Also, a sample of the outdoor air in central Örebro is taken to be able to conclude that the indoor pollution is indeed from indoor sources, using indoor/outdoor ratio (I/O ratio). To evaluate the risk associated with the measured concentrations of VOCs and aldehydes a new approach using chronic limit values for calculation of hazard index (HI) and maximum cumulative ratio (MCR) is used as well as the Swedish occupational exposure limits. HI is calculated by adding all substances in the mixture’s hazard quotients (HQs), which is the measured concentration divided by the limit value. The HI is an indication of the strength of the toxicity of the mixture where a value above 1 is of concern, whereas MCR is used to identify if one or several substances are responsible for the total toxicity by dividing the HI by the maximum HQ in the mixture. The results showed a low risk for all sampling sites, except personal sampling in salon 3, where HI &gt; 1 and MCR&gt;2, which means concern for combined effect by several substances. / Vi tenderar att spendera allt mer tid inomhus, vilket gör att vi konstant andas inomhusluft. I inomhusluft finns en mix av kemikalier från både luften utomhus som släpps in genom ventilationssystemen och från material och produkter vi använder inomhus. För att bibehålla god hälsa är det nödvändigt med en god kvalitet på inomhusluften, inte bara hemma utan också på jobbet. Vissa arbetsplatser löper större risk för dålig inomhusluft än andra, ett bra exempel är skönhetssalonger. Detta på grund av det stora antal produkter som används, varav alla har sin egen komplexa komposition av kemikalier. I denna studie mäts koncentrationerna av flyktiga organiska ämnen och aldehyder i inomhusluften på olika skönhetssalonger och ett gym. Tre olika skönhetssalonger deltog i studien; en hårsalong som använder sig av traditionella produkter, en hårsalong som använder ekologiska produkter och en nagelsalong. Gymmet används som en typ av referensanläggning där låga halter av flyktiga organiska ämnen och aldehyder väntas. Även utomhusluften mäts i centrala Örebro, och resultatet används för att kunna fastställa att de uppmätta ämnena har sitt ursprung i inomhusmiljön genom att beräkna indoor/outdoor ratio (I/O ratio). För att utvärdera riskerna de uppmätta koncentrationerna flyktiga organiska ämnen och aldehyder utgör, tillämpas ett nytt tillvägagångssätt där man använder kroniska gränsvärden för att beräkna hazard index (HI) och maximum cumulative ratio (MCR), samt svenska hygieniska gränsvärden. Alla ämnen i en mix har en så kallad hazard quotient (HQ) som beräknas genom att dividera den uppmätta koncentrationen av ämnet med dess gränsvärde. Alla ämnens HQ adderas och tillsammans utgör de HI. HI indikerar styrkan av mixens sammanvägda toxicitet och ett värde över 1 är oroväckande. MCR används för att identifiera om ett eller flera ämnen är ansvariga för den totala toxiciteten för mixen genom att dividera HI med den högsta uppmätta HQ i mixen. Resultaten visade låg risk för alla prover, förutom personburen provtagning i salong 3, där HI&gt;1 och MCR&gt;2, vilket betyder att oro finns för mixens kombinerade effekter och det orsakas av flera substanser.

Alkaline by-products were used in a leaching test to study their effect on highly weathered, sulphide-rich mine waste from Ljusnarsberg for the attempt to neutralize the leachate and immobilize trace metals through precipitation of secondary minerals. Leaching was performed at liquid/solid ratio of 0.5-20 with 10 % alkaline material. It was found that immobilization of trace elements (Cd, Pb, Zn and Cu) were successful in systems able to neutralize the mine waste. The systems with a lower pH increase (4-5) leached an increased amount of both Zn and Cd compared to the reference. Fly ashes are found to be the most effective material regarding pH and metal immobilization but are also found to have the highest increase of molybdenum and antimony, trace metals originating from the ashes. High chloride content is another concern regarding fly ashes, as high levels in the leachate would cause a concern for the nearby fresh water.