1,2-Diazetidine is a four-membered ring heterocyclic compound which has two adjacent nitrogen atoms. However, the syntheses of C-unsubstituted 1,2-diazetidines are rarely reported in the literature. C-unsubstituted 1,2-diazetidines were synthesized through an operationally simple intermolecular vicinal disubstitution reaction between 1,2-dibromoethane and hydrazine with N-arylsulfonyl as the protecting group. Several different types of C-unsubstituted 1,2-diazetidines derivatives were synthesized with either two of the same or two different N-arylsulfonyl groups. The electronic and steric properties were analyzed using Raman spectroscopy and computational calculations. Then, several synthetic applications were demonstrated with 1,2-ditosyl-1,2-diazetidine (DTD). As a synthetic application, a nucleophilic ring-opening reaction of the diazetidine was identified through various thiol selective cleavage of the N‒N bond, resulting in the stereoselective formation of a new class of N-sulfenylimine. Furthermore, DTD underwent FeBr2-catalyzed retro [2+2] ring-opening and sustained release of formaldimine (FI) in situ in a reaction medium which is the simplest imine used amidomethylative reagent. Therefore, the effective available concentration can be controlled at low levels in the reaction medium. Moreover, the sustained release of FI was able to interrupt the amidomethylative process with α- methylstyrene and FeBr2 as the catalyst and resulted in 4-phenyl-1,2,3,6-tetrahydropyrimidine (PTPH) as a product. The PTPH is a neurotoxic compound used to induce Parkinson’s disease in animal models. In addition, sustained release of FI allowed to switch the selectivity from alkene, imine, and imine arrangement into alkene, imine, and alkene arrangement in [2+2+2] cycloaddition reaction and led to form piperidines as a product which is the most observed heterocycle in marketed drug molecules. Chromane derivatives are observed in pharmaceuticals and natural products. Chirally pure chromane derivatives were synthesized through ruthenium-catalyzed chiral transient directing-mediated enantioselective C–H activation. Interestingly, a phosphate was involved in the deprotonation step, the rate-determining step with a 5.3 KIE value.

För att hitta en svensk motsvarighet till infant observation, eller naturalistic infant observation, har jag genomgående i denna studie använt begreppet spädbarnsobservationer. Begreppet refererar till Tavistockklinikens spädbarnsobservationer av barn, nyfödda upp till två och ett halvt års ålder. Syftet med studien har varit att utforska, undersöka och beskriva en spädbarnsobservation enligt Tavistockmodellen i ljuset av Sterns teori. Det är ofrånkomligt och har förefallit ytterst viktigt att beskriva och benämna mina egna upplevelser, erfarenheter och inställning till spädbarnsobservation. Samt att tolka och analysera dess eventuella betydelse för min kunskaps- och professionsutveckling i psykoterapeutiskt arbete som psykoterapeut. Studien är en kvalitativ studie, baserad på observation av ett nyfött barn upp till 1 ó års ålder samt dess relation till sin mor, far och syskon. Observationsmaterialet skrevs ned efter vart och ett av observations- tillfällena. Materialet analyserades genom Burnard´s (1991) stegvisa process De identifierade huvudrubrikerna är 1) Barnets utvecklingslinje 2) Förälderns utvecklingslinje 3) Samspelsutvecklingen 4) Min observatörsroll. Empirin belyses genom D. N. Sterns självutveckling. Spädbarnsobservationen var en enormt lärorik process. Klinisk kunskap om ett barns normal-utveckling är av stor betydelse. Vidare har min egen neutralitet och omedveten kommunikation betytt mycket för vidare psykoterapeutiskt arbete. Önskemål finns att genomföra fler spädbarnsobservationer för att bekräfta eller dementera erfarenheterna från nu gjord observation.

This thesis is concerned with various problems associated with the factorisation and feedback stabilisation of multidimensional linear discrete systems, which may be represented by rational matrices in several variables. Some factorisation techniques for polynomial and rational matrices in several variables have been explored and applied to the study of feedback stabilisation of multidimensional linear systems. The work presented here may be divided into two parts. The first part (Chapters 2 and 3) is concerned with two-dimensional systems, while the second part (Chapters 4 and 5) deals with three- and higher-dimensional systems. The emphasis of the first part is placed on the development of constructive algorithms for several kinds of factorisation of polynomial and rational matrices in two variables. In Chapter 2, an algorithm for obtaining primitive factorisation of polynomial matrices in two variables is developed, which is then followed by an algorithm for the decomposition of a rational matrix in two variables into factor coprime matrix fraction descriptions. Chapter 3 presents a procedure for the analysis and compensator design of two-dimensional feedback systems. A constructive algorithm for solving a Diophantine-type equation in two variables is derived. A necessary and sufficient condition for the feedback stabilisability of two-dimensional systems is obtained. The complete set of stabilising compensators for a given two-dimensional plant is then characterised. The role played by the matrix fraction description approach in the study of three- and higher dimensional systems, particularly with respect to the feedback stabilisation of these systems, is then investigated in detail in the second part. Chapter 4 deals with various kinds of factorisations for polynomial and rational matrices in three or more variables. For example, a criterion for the existence of primitive factorisation of a class of polynomial matrices in three or more variables is derived. By introducing a new concept: <i>generating polynomials</i>, it is shown that a direct generalisation of several existing results in two-dimensional systems theory to their higher-dimensional counterparts is not possible. In chapter 5, applying the generating polynomials, we obtain a stability test and a necessary and sufficient condition for feedback stabilisability of three- and higher-dimensional systems.

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“Matrix effects” in Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy are the spectroscopic changes induced by intermolecular interactions, providing sensitivity to local structure and order in solids and liquids. This project aims to identify the effect of intermolecular interactions caused by different n-alkane solid state structures on their NEXAFS spectra. Changes to the carbon 1s NEXAFS spectra are studied as a function of their solid state structure and organization. Two experimental approaches were proposed in this project. In the first approach, different n-alkane crystal structures (orthorhombic, monoclinic, etc.) are examined which arise as a function of n-alkane chain length. In the second approach, changes observed through the pre-melting point order-disorder phase transition found in n-alkanes are examined. This work will explore the characteristic spectroscopic differences observed between n-alkanes in different crystalline forms as well as in the disordered phase below the melting points. In this project, well-ordered diamond shape n-alkane single crystals were obtained by solution casting, using experimental conditions optimized for each n-alkane. As circularly polarized radiation will average the effect of molecular orientation, circularly polarized radiation was used to obtain the NEXAFS spectra of n-alkanes. However, in the analysis of the NEXAFS spectra of n-alkanes recorded with the left circularly polarized X-rays, a significant linear polarization contamination was found. Therefore, linearly polarized X-rays were used to acquire angle dependent NEXAFS spectra, where the X-ray polarization was deliberately aligned along the principal axes (X, Y) of the n-alkane crystal. It was observed that the room temperature carbon 1s NEXAFS spectrum of n-octacosane (C28H58) was different from that of the other n-alkanes, n-tetracosane (C24H50), n-tricosane (C23H48) and n-tetracontane (C40H82). This difference can be attributed due to the different crystal packing of n-octacosane (C28H58 - monoclinic) relative to the other n-alkanes (triclinic and orthorhombic), suggesting different intermolecular interactions (matrix effects) in n-octacosane (C28H58). The analysis of the temperature dependent NEXAFS spectra of n-alkanes reveals that samples of the short chain n-alkane crystals, specially n-tricosane (C23H48), n-tetracosane (C24H50) and n-octacosane (C28H58), sublimed in the STXM microscope. Changes observed in the carbon 1s NEXAFS spectra of n-tetracontane (C40H82) with temperature were attributed to the order-disorder transition. This further illustrates the existence of matrix effects in the NEXAFS spectra of n-alkanes.

The versatility of N-heterocyclic carbenes (NHCs) is demonstrated by numerous practical applications in homogeneous transition metal catalysis, organocatalysis and materials science. There remains a paucity of electropositive metal NHC complexes and so this chemistry is poorly developed with respect to that of the late transition metal and main group elements. This thesis describes the synthesis of new alkoxy-tethered NHC proligands, their use in the synthesis of reactive metal amide and metal alkyl complexes, and finally small molecule activation using these complexes. Chapter One introduces NHCs and discusses their use as supporting ligands for early transition metal and f-block complexes. Small molecule activation using organometallic complexes is examined alongside the use of electropositive metal NHC complexes in catalysis. Chapter Two contains the synthesis and characterisation of new alkoxy-tethered NHC proligands and a variety of electropositive MII (M = Mg and Zn), MIII (M = Y, Sc, Ce and U) and MIV (M = Ce and U) amide complexes. X-ray diffraction studies and a DFT study are used to probe the extent of covalency in the bonding of the MIV complexes. Chapter Three investigates the reactivity of the amide complexes prepared in Chapter Two. The MII complexes are shown to be initiators for the polymerisation of raclactide into biodegradable polymers. The MIII complexes are used to demonstrate additionelimination reactivity of polar substrates across the M-Ccarbene bond which allows the formation of new N-E (E = Si, Sn, P or B) bonds. Treatment of the UIII silylamide complex U(N{SiMe3}2)3 with CO results in the reductive coupling and homologation of CO to form an ynediolate core -OC≡CO- and the first example of subsequent reactivity of the ynediolate group. The MIV complexes are used to examine the potential for forming MIV cationic species and alkyl complexes. Chapter Four examines the synthesis of MIII (M = Ce and Sc) aminobenzyl complexes and MIII (M = Y, Sc and U) neosilyl and neopentyl alkyl complexes. The addition-elimination reactivity discussed in Chapter Three is extended to include C-E bond formation (E = Si, Sn, P, B, I or C). Chapter Five provides overall conclusions to the work presented within this thesis. Chapter Six gives experimental and characterising data for all complexes and reactions in this work.

Knowledge of the relationship between rate of nitrification and nitrous oxide (N2O) emission, and between cumulative nitrification and N2O emission is important for developing N2O emission mitigation strategies. Gross nitrification and N2O from nitrification were determined using 15N labelling of inorganic N. N-Serve was added to delay nitrification and results showed an increase in rate of N2O emission with that of apparent nitrification in absence of N-Serve, but there was no relation in its presence. Same amount of cumulative N2O was emitted for same amount of nitrogen (N) apparently nitrified, regardless of N-Serve addition. There was no relation between N2O emission attributed to nitrification and gross nitrification with and without N-Serve. Again, same amount of cumulative N2O was emitted for same amount of gross nitrified N, regardless of N-Serve addition. These results imply that the amount of N nitrified dictates eventual cumulative N2O emitted, regardless of rate of nitrification. / February 2017