AUTOMATED FLOW INJECTION INSTRUMENTATION FOR MONITORING NITROGEN SPECIES IN NATURAL WATERS

The provision of high quality analytical data is an essential prerequisite for understanding the biogeochemical cycling of nutrients in the aquatic environment. Due to the instability of samples collected for nutrient determinations however, in situ analysis is preferred. This approach also allows for high temporal and spatial resolution of the data and alteration of the sampling frequency to meet local environmental needs. Chapter One describes the role of nitrogen species, particularly ammonia and nitrate, in the aquatic environment, their sources, and possible environmental effects and summarises analytical techniques for their determination. Solid state miniaturised detectors and their suitability for in situ monitoring are also discussed. The characterisation and evaluation of a miniature Ocean Optics PSD - 1000 spectrometer and its suitability for field deployment is described in Chapter Two. Parameters investigated were optical resolution, wavelength repeatability, photometric linearity and instrumental noise and drift. The incorporation of the Ocean Optics PSD - 1000 miniature spectrometer into a gas diffusion Flow Injection (Fl) manifold for the determination of ammonia in natural waters is detailed in Chapter Three. Optimisation of the Fl parameters and analytical performance are discussed in detail. The development of an immobilised pH indicator and adaptation to a laminar Fl manifold is also considered. Chapter Four describes the use of the miniature spectrometer in a Fl manifold for the determination of nitrate and nitrite, with analytical figures of merit detailed. The increased information potential of the spectrometer (i.e. full spectral acquisition) facilitated the removal of the refractive index problem using dual wavelength correction. Miniaturisation and automation of the optimised nitrate manifold using micro-solenoid pumps and LabView™ graphical programming is described in Chapter Five. Field deployment of the automated system was assessed during a six week British Schools Exploring Society Expedition to Lesotho, S. Africa (in which an intensive biogeochemical survey of the Sehlabathebe National Park was conducted) and a three day campaign on the River Frome, Dorset, U.K. Chapter Six details the ion chromatographic analysis of major anions and cations (including ammonium and nitrate) in precipitation samples. Two sampling campaigns were conducted. One was at an urban site (Plymouth City Centre) from 27/01/98 - 11/05/98, and the influence of aerosol source on the chemical composition of Plymouth precipitation is discussed. The other involved the Austrian precipitation network and wet deposition trends for nitrate, ammonium and sulphate are discussed. The multivariate analysis technique of PCA was applied to both environmental datasets and the interpretation and merits of this statistical approach are considered.M Squared Technology Limited. Totne

Investigating the use of Virtual Learning Environments by teachers in schools and colleges

Investigating the use of Virtual Learning Environments by teachers in schools and college

Synthesis, structural characterisation and solution behaviour of high symmetry lanthanide triflate complexes with the sterically demanding phosphine oxides Cy3PO and tBu3PO

The synthesis and characterisation of lanthanide trifluoromethane sulfonate (Ln(OTf)3) complexes with tricyclohexylphosphine oxide, (Cy3PO) and tritert-butylphosphine oxide, (tBu3PO) is described. The structures of [Ln(H2O)5(Cy3PO)2].2R3PO.[OTf]3 (Ln = Pr, Tm R = Cy Ln = Nd R = tBu) are pentagonal bipyramidal with an equatorial plane of five H2O and two axial Cy3PO. The remaining Cy3PO molecules are hydrogen bonded to the coordinated water molecules as are the triflate anions. Solution NMR spectroscopy shows the triflate ions remain associated with the complexes in CDCl3 solution. Lanthanide induced shifts in the 19-F and 31-P NMR spectra confirm that one structure is present for all the lanthanides with an additional structure for the heavier metals. The acidity of the complexes has been examined by 31-P NMR spectroscopy of the reactions between [Ln(H2O)5(Cy3PO)2].2Cy3PO.[OTf]3 (Ln = La, Eu, Er, Lu) and phosphines PR3 (R = Ph, mesityl and Cy) and Ph2PC2H4PPh2 and Ph2PC3H6PPh2 . Protonation of the more basic phosphines and H-bonding to the less basic phosphines is observed

Constructing chiral MOFs by functionalizing 4,2′:6′,4″-terpyridine with long-chain alkoxy domains: rare examples of neb nets

Reactions of 4′-(4- n alkyloxyphenyl)-4,2′:6′,4″-terpyridines (alkyl = hexyl or nonyl) with CoIJNCS) 2 lead to three structurally characterized chiral 3D assemblies which adopt rare neb topologies. For the n hexyl-functionalized ligands, both enantiomorphic lattices of the neb nets (crystallizing in the tetragonal space groups P4 1 2 1 2 and P4 3 2 1 2, respectively) are presente

Competitive formation of spiro and ansa derivatives in the reactions of tetrafluorobutane-1,4-diol with hexachlorocyclotriphosphazene: a comparison with butane-1,4-diol

Reaction of hexachlorocyclotriphosphazene, N3P3Cl6 (1), in two stoichiometries (1:1.2 and 1:3) with the sodium derivative of the fluorinated diol, 2,2,3,3-tetrafluorobutane-1,4-diol, (2), in THF solution at room temperature afforded six products, whose structures have been characterized by X-ray crystallography and 1H, 19F and 31P NMR spectroscopy: the mono-spiro compound, N3P3Cl4(OCH2CF2CF2CH2O), (3), its ansa isomer, (4), a di-spiro derivative N3P3Cl2(OCH2CF2CF2CH2O)2, (5), its spiro-ansa (6) and non-gem cis bis-ansa (7) isomers and a tri-spiro compound N3P3(OCH2CF2CF2CH2O)3, (8). The tri-spiro derivative (8) was also formed in the reaction of the ansa compound (4) with diol (2) in a 1:3 ratio in THF at room temperature. The reactions of (1) with step-wise additions of (2) were also investigated at low temperature (-780C) to give the same range of products as at room temperature. The results of all reactions are compared with previous work on the reactions of (1) with butane-1,4-diol/pyridine mixtures and with the reaction of hexafluorocyclotriphosphazene, N3P3F6 (9), with the silyl derivative of the diol (2), (Me3SiOCH2CF2)2, in a 1:0.4 mole ratio in the same solvent, THF

The Pragmatic Vision of Visionary Pragmatism: The Challenge of Radical Democracy in a Neoliberal World Order

Visionary Pragmatism is a project formulated in the face of a hyper-malignant mode of capitalism that is provoking and entangled with ecological collapse, dedemocratization, unfathomable inequality, destruction of the commons, intensifying xenophobia, and racism. In the book, I seek modes of radical and ecological democracy that advance beyond both modest resistance and radical posturing that is largely empty and formulaic. I explore possibilities for generating new political modes in a variety of locations, and especially at the intersections where democratic initiatives in higher education engage with myriad publics to intensify alternative processes of knowledge production, political practice, and power that are sufficiently game-transformative in their own right to stand a chance of generating radical change. Beyond myopic pragmatism and hyper-professionalized scholarship, ‘visionary pragmatism’ offers a path along which we might refashion more imaginative theory through modes of creatively engaged practice and, in turn, more radical politics in conjunction with theory thus generated and critical theory broadly construed. Stylistically, the book moves between theoretical reflection and ethnography

Performance characteristics of a low-cost, field-deployable miniature CCD spectrometer

Miniature spectrometers incorporating array detectors are becoming a viable, low-cost option for field and process deployments. The performance characteristics of one such instrument are reported and compared with those of a conventional benchtop instrument. The parameters investigated were wavelength repeatability, photometric linearity, instrumental noise (photometric precision) and instrumental drift

Mononuclear Transition Metal Complexes of 7-Nitro-1,3,5-Triazaadamantane

This is the peer reviewed version of the following article: Wagner, G., Horton, P. N., & Coles, S. J. (2016). Mononuclear Transition Metal Complexes of 7-Nitro-1,3,5-Triazaadamantane. ChemistrySelect, 1(8), 1548-1555. DOI: 10.1002/slct.201600502, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/slct.201600502/abstract. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingComplexes of the type [MCl2(7-nitro-1,3,5-triaza-adamantane)2] (M = Zn(II), Pd(II), Pt(II)) and [MCl2(H2O)2(7-nitro-1,3,5-triazaadamantane) 2] (M = Mn (II), Co(II), Ni(II)) have been prepared and their structures have been analysed by X-ray crystallography, elemental analysis, IR and solid state 13C and 15N NMR spectroscopy, supported by density functional theory/ gauge independent atomic orbital (DFT/GIAO) calculations. In each case, 7-nitro-1,3,5-triazaadamantane acts as a mono-dentate ligand and binds to one metal centre only, in spite of the presence of three equivalent amino nitrogens. In the Co(II) and Ni(II) complexes, a two-dimensional intermolecular hydrogen bonding network between the aqua- and the chloro ligands is established. The uncoordinated amines of the 7-nitro-1,3,5-triaza- adamantane are not involved in any H-bonding, as a result of the exceptionally low basicity of this compound

Regioswitchable palladium-catalyzed decarboxylative coupling of 1,3-dicarbonyl compounds

A palladium-catalyzed chemo- and regioselective coupling of 1,3-dicarbonyl compounds via an allylic linker has been developed. This reaction, which displays broad substrate scope, forms two C−C bonds and installs two all-carbon quaternary centers. The regioselectivity of the reaction can be predictably controlled by utilizing an enol carbonate of one of the coupling partners