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Apatites are a diverse class of phosphate minerals that are important in a great variety of natural and industrial processes. They are, for example, used as raw material in fertiliser production and in the remediation of metal-contaminated soils. Hydroxyapatite Ca5(PO4)3OH, (HAP) and fluorapatite Ca5(PO4)3F, (FAP) are similar to the biological apatite that is the main constituent of mammalian bone and teeth, and they are therefore promising materials for artificial bone and tooth implants. This thesis is a summary of four papers with focus on dissolution and surface complexation reactions of HAP and FAP in the absence and presence of both organic ligands and the natural and commonly occurring iron oxide goethite (α-FeOOH). The dissolution and surface complexation of HAP and FAP was investigated with a combination of different techniques. Potentiometric acid/base titrations and batch experiments were combined with X-ray Photoelectron Spectroscopy (XPS) and Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectroscopy to generate dissolution and surface complexation models for both apatites. The results from these studies showed that both apatites form surface layers that are different from their bulk compositions when equilibrated in aqueous solutions. The modeling efforts predicted speciation of these surfaces as well as the concentration of the dissolution products in the solution. The interaction between organic ligands and the apatite surfaces was also investigated and the results from this study show that the organic ligands form outer-sphere complexes on the apatite surfaces over a large pH interval, and that this adsorption enhances the dissolution of apatites. The presence of goethite also enhances the dissolution of FAP as it acts as a sink for the phosphate released from FAP. Phase transformation in this system was detected using ATR-FTIR as the phosphate adsorbed to the goethite surface precipitates as FePO4 (s) after approximately 15 days of reaction time. This changes the speciation, and possibly also the bioavailability of phosphate in this two-mineral system.

Mechanistic studies on three different ruthenium-based catalysts have been performed. The catalysts have in common that they have been employed in hydrogen transfer reactions involving alcohols and ketones, amines and imines or both. Bäckvall’s catalyst, η5-(Ph5C5)Ru(CO)2Cl, finds its application as racemization catalyst in dynamic kinetic resolution, where racemic alcohols are converted to enantiopure acetates in high yields. The mechanism of the racemization has been investigated and both alkoxide and alkoxyacyl intermediates have been characterized by NMR spectroscopy and in situ FT-IR measurements. The presence of acyl intermediates supports a mechanism via CO assistance. Substantial support for coordination of the substrate during the racemization cycle is provided, including exchange studies with both external and internal potential ketone traps. We also detected an unexpected alkoxycarbonyl complex from 5-hydroxy-1-hexene, which has the double bond coordinated to ruthenium. Shvo’s catalyst, [Ru2(CO)4(μ-H)(C4Ph4COHOCC4Ph4)] is a powerful catalyst for transfer hydrogenation as well as for dynamic kinetic resolution. The mechanism of this catalyst is still under debate, even though a great number of studies have been published during the past decade. In the present work, the mechanism of the reaction with imines has been investigated. Exchange studies with both an external and an internal amine as potential traps have been performed and the results can be explained by a stepwise inner-sphere mechanism. However, if there is e.g. a solvent cage effect, the results can also be explained by an outer-sphere mechanism. We have found that there is no cage effect in the reduction of a ketone containing a potential internal amine trap. If the mechanism is outer-sphere, an explanation as to why the solvent cage effect is much stronger in the case of imines than ketones is needed. Noyori’s catalyst, [p-(Me2CH)C6H4Me]RuH(NH2CHPhCHPhNSO2C6H4-p-CH3), has successfully been used to produce chiral alcohols and amines via transfer hydrogenation. The present study shows that the mechanism for the reduction of imines is different from that of ketones and aldehydes. Acidic activation of the imine was found necessary and an ionic mechanism was proposed.

Syftet med denna uppsats är att kritiskt granska leksaksreklam riktad till barn. Genom att använda oss av reklamklipp från det sociala mediet YouTube vill vi undersöka hur manligt respektive kvinnligt samt heteronormativitet konstrueras i dessa. För att finna mönster som vi kan koppla till vårt syfte tittar vi ur ett genusperspektiv genom textanalys närmare på reklamklippen. Genom vår analys fann vi att leksaksreklam riktad till barn är påtaglig könsstereotyp och skapar förväntningar på barn hur de ska se ut samt vilka egenskaper de förväntas inneha. Vi fann också att reklamklippen reproducerar heterosexualiteten som den hegemoniska sexualiteten. Detta gör att heteronormativiteten blir stark i reklamklipen då samtliga reklamklipp riktade till flickor vi tittat på är byggda på en parrelation mellan en man och en kvinna. Nyckelord: Genus, heteronormativitet, maskulinitet, könsroller, leksaker, den inre och yttre sfären, arbetsdelningen, passiv och aktiv, rosa. / English title: Boys are strong, girls are pink - a study of toy advertising to children. The purpose of this study was to critically examine the toy advertising to children. Through the use of commercials from the social media YouTube, we wanted to examine how male or female and heteronormativity were socially constructed in them. Through text analysis, we looked closer at the commercials with a gender perspective in order to find patterns that we could connect to our purpose. Through our analysis we found that toy advertising to children is reproducing gender stereotypes creating expectations for children how they should look and what features they expected to hold. We also found that the commercials reproduce heterosexuality as the hegemonic sexuality, as all commercials aimed at girls we looked at reproduces the partnership between two individuals as a relationship between a man and a woman. Keywords: gender, heteronormativity, masculinity, gender roles, toys, the inner and outer sphere of labor, passive and active, pink.

Late transition metal complexes of silver(I), rhodium(I), ruthenium(II), palladium(II) and platinum(II) containing a nitrile-functionalized N-heterocyclic carbene ligand (C-CN) were prepared. The nitrile group on the C–CN ligand was shown to undergo hydrolysis under basic conditions, leading to a silver(I) carbene complex with a primary-amido functional group, and a trimetallic complex of palladium(II) with a partially hydrolyzed C–N–N–C donor ligand. The reduction of a nitrile-functionalized imidazolium salt in the presence of nickel(II) chloride under mild conditions yielded an axially chiral square-planar nickel(II) complex containing a unique primary-amino functionalized N-heterocyclic carbene ligand (C-NH2). A transmetalation reaction moved this chelating C–NH2 ligand from nickel(II) to ruthenium(II), osmium(II), and iridium(III), yielding important catalysts for the hydrogenation of polar double bonds. The ruthenium(II) complex, [Ru(p-cymene)(C–NH2)Cl]PF6 catalyzed the transfer and H2-hydrogenation of ketones. The bifunctional hydride complex, [Ru(p-cymene)(C–NH2)H]PF6, which contains a Ru–H/N–H couple showed no activity under catalytic conditions unless when activated by a base. The outer-sphere mechanism involving bifunctional catalysis of ketone reduction is disfavored according to experimental and theoretical studies and an inner-sphere mechanism is proposed involving the decoordination of the amine donor from the C–NH2 ligand. The ruthenium(II) complex [RuCp*(C–NH2)py]PF6 showed higher activity than the iridium(III) complex [IrCp*(C–NH2)Cl]PF6 in the hydrogenation of ketones. This ruthenium(II) complex also catalyzes the hydrogenation of an aromatic ester, a ketimine, and the hydrogenolysis of styrene oxide. We proposed an alcohol-assisted outer sphere bifunctional mechanism for both systems based on experimental findings and theoretical calculations. The cationic iridium(III) hydride complex, [IrCp*(C–NH2)H]PF6 , was prepared and this failed to react with a ketone in the absence of base. The crucial role of the alkoxide base was demonstrated in the activation of this hydride complex in catalysis. Calculations support the proposal that the base deprotonates the amine group of this hydride complex and triggers the migration of the hydride to the η5-Cp* ring producing a neutral iridium(I) amido complex. This system contains an active Ir–H/N–H couple required for the outer sphere hydrogenation of ketones in the bifunctional mechanism.

Late transition metal complexes of silver(I), rhodium(I), ruthenium(II), palladium(II) and platinum(II) containing a nitrile-functionalized N-heterocyclic carbene ligand (C-CN) were prepared. The nitrile group on the C–CN ligand was shown to undergo hydrolysis under basic conditions, leading to a silver(I) carbene complex with a primary-amido functional group, and a trimetallic complex of palladium(II) with a partially hydrolyzed C–N–N–C donor ligand. The reduction of a nitrile-functionalized imidazolium salt in the presence of nickel(II) chloride under mild conditions yielded an axially chiral square-planar nickel(II) complex containing a unique primary-amino functionalized N-heterocyclic carbene ligand (C-NH2). A transmetalation reaction moved this chelating C–NH2 ligand from nickel(II) to ruthenium(II), osmium(II), and iridium(III), yielding important catalysts for the hydrogenation of polar double bonds. The ruthenium(II) complex, [Ru(p-cymene)(C–NH2)Cl]PF6 catalyzed the transfer and H2-hydrogenation of ketones. The bifunctional hydride complex, [Ru(p-cymene)(C–NH2)H]PF6, which contains a Ru–H/N–H couple showed no activity under catalytic conditions unless when activated by a base. The outer-sphere mechanism involving bifunctional catalysis of ketone reduction is disfavored according to experimental and theoretical studies and an inner-sphere mechanism is proposed involving the decoordination of the amine donor from the C–NH2 ligand. The ruthenium(II) complex [RuCp*(C–NH2)py]PF6 showed higher activity than the iridium(III) complex [IrCp*(C–NH2)Cl]PF6 in the hydrogenation of ketones. This ruthenium(II) complex also catalyzes the hydrogenation of an aromatic ester, a ketimine, and the hydrogenolysis of styrene oxide. We proposed an alcohol-assisted outer sphere bifunctional mechanism for both systems based on experimental findings and theoretical calculations. The cationic iridium(III) hydride complex, [IrCp*(C–NH2)H]PF6 , was prepared and this failed to react with a ketone in the absence of base. The crucial role of the alkoxide base was demonstrated in the activation of this hydride complex in catalysis. Calculations support the proposal that the base deprotonates the amine group of this hydride complex and triggers the migration of the hydride to the η5-Cp* ring producing a neutral iridium(I) amido complex. This system contains an active Ir–H/N–H couple required for the outer sphere hydrogenation of ketones in the bifunctional mechanism.

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