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Dataset in support of the Southampton doctoral thesis 'Thin film thermoelectric materials and generators deposited by chemical vapour processes'
No full textThis dataset includes various data relating to the characterisation of various deposited thermoelectric thin films (i.e. GeTe, WS2xSe2-2x, and AZO). Thin films were characterised by SEM, EDX, XRD, XPS, Raman, AFM, Hall and Seebeck measurements. Further details of the dataset can be found in the README files attached.</span
Dataset in support of the journal article 'Synthesis, characterization and computational studies on gallium(III) and iron(III) complexes with a pentadentate macrocyclic bis-phosphinate chelator and their investigation as molecular scaffolds for 18F binding '
No full textxyz coordinates for various DFT complexes calculated in this paper to be published in Inorganic Chemistry https://doi.org/10.1021/acs.inorgchem.3c03135</span
Automating the production of [Fe<sup>18</sup>FF<sub>2</sub>(BnMe<sub>2</sub>-tacn)] and investigating radiostabilisers for use with high-activity [<sup>18</sup>F]F<sup>−</sup>
No full textThe manual radiofluorination and purification of [FeF3(BnMe2-tacn)] (tacn = 1,4,7-triazacyclononane) using 18F− in aqueous EtOH has been translated to a GE FASTLab™ automatic synthesis platform and optimised by conducting a series of low-activity radiolabelling experiments to explore the effects of varying the precursor concentration, temperature, heating time, addition of NaOAc buffer and EtOH:H2O ratio. The optimal conditions were determined to be 1 mg/mL of the precursor being heated at 120 °C for 10 min in 75 %:25 % EtOH:H2O containing 18F−, with elution using 10 mM NaOAc, giving 61 % radiochemical yield (RCY). These conditions were then employed with high-activity 18F− giving a 97 % radiochemical purity (RCP) at t = 0, which decreases by 22 % over 5 h. Sodium ascorbate, nicotinamide and p-benzoic acid (pABA) were then tested as potential radiostabilisers for this system, initially using low-activity 18F−. These experiments revealed very rapid defluorination of the radioproduct in the presence of sodium ascorbate. In contrast, both nicotinamide and pABA appear to be effective radiostabilisers, resulting in RCP values of 91 % and 89 %, respectively, after 2 h, which compare with an RCP of 81 % under analogous conditions at t = 2 h in their absence. High-activity experiments were then undertaken with addition of 5 mg/mL of nicotinamide, with a radio-active concentration (RAC) of 220 MBq/mL, giving RCY of 26 % and following purification, RCP values for the [Fe18FF2(BnMe2-tacn)] product of 97 % at t = 0 and 86 % after 3 h
Synthesis, characterization and computational studies on gallium(III) and iron(III) complexes with a pentadentate macrocyclic bis-phosphinate chelator and their investigation as molecular scaffolds for <sup>18</sup>F binding
No full textWith the aim of obtaining improved molecular scaffolds for 18F binding for use in PET imaging, gallium(III) and iron(III) complexes with a macrocyclic bis-phosphinate chelator have been synthesized, and their properties, including their fluoride binding ability, investigated.Reaction of Bn-tacn (1-benzyl-1,4,7-triazacyclononane) with paraformaldehyde and PhP(OR)2 (R = Me or Et) in refluxing THF, followed by acid hydrolysis yields the macrocyclic bis(phosphinic acid) derivative, H2(Bn-NODP) (1-benzyl-4,7-phenylphosphinic acid-1,4,7-triazacyclononane), which is isolated as its protonated form, H2(Bn-NODP)·2HCl·4H2O, at low pH (HClaq), its disodium salt, Na2(Bn-NODP)·5H2O at pH 12 (NaOHaq) or the neutral H2(Bn-NODP) under mildly basic conditions (Et3N). A crystal structure of H2(Bn-NODP)·2HCl·H2O confirmed the ligand’s identity. The mononuclear [GaCl(Bn-NODP)] complex was prepared by treatment of either the HCl or sodium salt with Ga(NO3)3·9H2O or GaCl3, while treatment of H2(Bn-NODP)·2HCl·4H2O with FeCl3 in aqueous HCl gives [FeCl(Bn-NODP)]. Addition of 1 mol. equiv. of aqueous KF to these chloro complexes readily forms the [MF(Bn-NODP)] analogues. Spectroscopic analysis on these complexes confirms pentadentate coordination of the doubly deprotonated (bis-phosphinate) macrocycle via its N3O2 donor set, with the halide ligand completing a distorted octahedral geometry; this is further confirmed through a crystal structure analysis on [GaF(Bn-NODP)]·4H2O. The complex adopts the geometric isomer in which the phosphinate arms are coordinated unsymmetrically (isomer 1) and with the stereochemistry of the three N atoms of the tacn ring in the RRS configuration, denoted (N)RRS, and the phosphinate groups in the RR stereochemistry, denoted (P)RR, (isomer 1/RR), together with its (N)SSR (P)SS enantiomer. The greater thermodynamic stability of the isomer over the other possible isomers is also indicated by density functional theory (DFT) calculations.Radiofluorination experiments on the [MCl(Bn-NODP)] complexes in partially aqueous MeCN/NaOAcaq (Ga) or EtOH (Ga or Fe; i.e. without buffer) with 18F− target water at 80°C/10 mins. lead to high radiochemical incorporation (radiochemical yields 60-80% at 1 mg/mL, or ~1.5 μM, concentration of the precursor). While the [Fe18F(n-NODP)] is unstable (loss of 18F−) in both H2O/EtOH and PBS/EtOH (PBS = phosphate buffered saline), the [Ga18F(Bn-NODP)] radioproduct shows excellent stability, RCP = 99% at t = 4 h (RCP = radiochemical purity) when formulated in 90%:10% H2O:EtOH and ca. 95% RCP over 4 h when formulated in 90%:10% PBS:EtOH. This indicates that the new ‘GaIII(Bn-NODP)’ moiety is a considerably superior fluoride binding scaffold than the previously reported [Ga18F(Bn-NODA)] (Bn-NODA = 1-benzyl-4,7-dicarboxylate-1,4,7-triazacyclononane), which undergoes rapid and complete hydrolysis in PBS/EtOH (ref. Chem. Eur. J. 2015, 21, 4688-4694).<br/
Datatset for the journal article 'Tungsten dichalcogenide WS2xSe2-2x films via single source precursor low-pressure CVD and their (thermo-)electric properties'
No full textData in support of the journal article published in Journal of Materials Chemistry A
This dataset contains:
The raw data of figure 3 to 8.
The figures are as follows:
Figure 3. Grazing incidence X-ray diffraction patterns of the as-deposited WS2xSe2-2x films from (1)-(4).
Figure 4. Raman spectral scan presented over a range of 50-450 cm-1, of the as-deposited WS2xSe2-2x. films.
Figure 5. Elemental XPS scans of (a) W 4f, (b) Se 3d and (c) S 2p for all as-deposited WS2xSe2-2x films deposited from precursors (1)–(4). (d) Composition of all the as-deposited films deposited from precursors (1)–(4).
Figure 6. (a) Temperature-dependent electrical conductivity, (b) Arrhenius plot for WS2xSe2-2x films deposited from precursors (1)-(4). (c) Electrical conductivity and (d) Hall measurements against the chalcogenide content of the films.
Figure 7. (a) Carrier concentration and (b) carrier mobility of the as-deposited binary films, WS2 (red) and WSe2 (orange). Compared with the films annealed at 500oC in the respective chalcogenide atmospheres.
Figure 8. Temperature-dependent (a) Seebeck, and (b) power factor measurements for the WS2xSe2-2x films deposited from precursors (1)-(4).</span
Ultralow thermal conductivity and improved thermoelectric properties of Al-doped ZnO by In Situ O<sub>2</sub> plasma treatment
No full textThe thriving of Internet-of-Things and integrated wireless sensor networks has brought an unprecedented demand for sustainable micro-Watt-scale power supplies. Development of high-performing micro-thermoelectric generator (μ-TEG) that can convert waste thermal energy into electricity and provide sustainable micro-Watt-scale power is therefore extremely timely and important. Herein, a significant advance in the development of earth-abundant, nontoxic thermoelectric materials of aluminium-doped zinc oxide (AZO) is presented. Through nanostructure engineering using a novel in situ O2 plasma treatment, AZO films are demonstrated with ultralow thermal conductivity of 0.16 W m-1 K-1 which is the lowest reported in the literature. This nanostructured film yields a power factor of 294 μW m-1K-2 at 563 K and has resulted in a state-of-the-art ZT of 0.11 at room temperature and 0.72 at 563 K for AZO thin films. Furthermore, the fabrication and testing of a prototype lateral μ-TEG are reported based on the AZO thin film which achieves a power output of 1.08 nW with an applied temperature difference of 16.9 °C
Dataset in support of the journal article 'Ultra-low thermal conductivity and improved thermoelectric properties of Al-doped ZnO by in-situ O2 plasma treatment'
No full textThe thriving of Internet-of-Things and integrated wireless sensor networks has brought an unprecedented demand for sustainable micro-Watt-scale power supplies. Development of high-performing micro-thermoelectric generator (μ-TEG) that can convert waste thermal energy into electricity and provide sustainable micro-Watt-scale power is therefore extremely timely and important. Herein, a significant advance in the development of earth-abundant, nontoxic thermoelectric materials of aluminium-doped zinc oxide (AZO) is presented. Through nanostructure engineering using a novel in situ O2 plasma treatment, AZO films are demonstrated with ultralow thermal conductivity of 0.16 W m-1 K-1 which is the lowest reported in the literature. This nanostructured film yields a power factor of 294 μW m-1K-2 at 563 K and has resulted in a state-of-the-art ZT of 0.11 at room temperature and 0.72 at 563 K for AZO thin films. Furthermore, the fabrication and testing of a prototype lateral μ-TEG are reported based on the AZO thin film which achieves a power output of 1.08 nW with an applied temperature difference of 16.9 °C. </span
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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