Search results for "XAS"
showing 10 items of 49 documents
Understanding the Conversion Process of Magnetron-Deposited Thin Films of Amorphous ReO$_x$ to Crystalline ReO$_3$ upon Thermal Annealing
2020
Crystal growth & design 20(9), 6147 - 6156 (2020). doi:10.1021/acs.cgd.0c00848
Geochemical Interactions of Plutonium with Opalinus Clay Studied by Spatially Resolved Synchrotron Radiation Techniques
2017
Plutonium plays an important role within nuclear waste materials because of its long half-life and high radiotoxicity. The aim of this study was to investigate with high spatial resolution the reactivity of the more oxidized forms of Pu(V,VI) within Opalinus Clay (OPA) rock, a heterogeneous, natural argillaceous rock considered as a potential repository host. A combination of synchrotron based X-ray microprobe and bulk techniques was used to study the spatial distribution and molecular speciation of Pu within OPA after diffusion and sorption processes. Microscopic chemical images revealed a pronounced impact of geochemical heterogeneities concerning the reactivity of the natural barrier mat…
Ecological divergence of closely related Diplostomum (Trematoda) parasites.
2006
Parasite life-cycles present intriguing model systems to study divergence in resource use and ecology between parasite taxa. In ecologically similar taxa, consistent selective forces may lead to convergence of life-history traits, but resource overlap and similarity of life-cycles may also promote divergence between the taxa in (1) use of host species or (2) specific niche within a host. We studied the life-history characteristics of 2 sympatric species of Diplostomum parasites, D. spathaceum and D. gasterostei, concentrating particularly on differences in intermediate host use and characteristics of the infective stages between the species. This group of trematodes is a notoriously difficu…
Rational assembly and dual functionalization of Au@MnO heteroparticles on TiO2 nanowires
2014
Au–MnO heteroparticles were immobilized on the surface of TiO2 nanowires and tagged subsequently with a fluorescent ligand. The immobilization of the Au@MnO heteroparticles was achieved by functionalizing the TiO2 nanowire support with a polymer containing catechol anchor groups for binding to the metal oxide surface and amine groups for conjugation to the Au domains of the Au@MnO heteroparticles. The Au domain of the resulting TiO2@Au–MnO nanocomposite could be functionalized selectively with a thiol-tagged 24 mer oligomer containing Texas red (SH-ODN-TXS red), whereas a green dye (NBD–Cl) could be anchored selectively to the TiO2 “support” using the free amine groups of the polymeric liga…
Mn, Fe, Zn and As speciation in a fast-growing ferromanganese marine nodule
2004
The speciation of Mn, Fe, As and Zn in a fast-growing (0.02mm/yr), shallow-marine ferromanganese nodule has been examined by micro X-ray fluorescence, micro X-ray diffraction, and micro X-ray absorption spectroscopy. This nodule exhibits alternating Fe-rich and Mn-rich layers reflecting redox variations in water chemistry. Fe occurs as two-line ferrihydrite. The As is strictly associated with Fe and is mostly pentavalent, with an environment similar to that of As sorbed on or coprecipitated with synthetic ferrihydrite. The Mn is in the form of turbostratic birnessite with ~;10 percent trivalent manganese in the layers and probably ~;8 percent corner-sharing metal octahedra in the interlayer…
"Salvation from unhappines by doing one's best" : a rhetorical analysis on Joel Osteen's sermons in the light of the US culture and values
2014
Tiivistelmä – Abstract Tämä laadullinen tutkimus keskittyy Joel Osteenin saarnoihin. Hän johtaa maan suurinta seurakuntaa, Lakewood-kirkkoa Texasin Houstonissa, USA:ssa. Tutkielma pyrkii vastaamaan kahteen tutkimuskysymykseen: 1) Mitkä ovat Osteenin eniten käyttämät retoriset keinot, ja kuinka ne näkyvät hänen saarnoissaan? 2) Miten Osteen käyttää hyväkseen kristillisiä oppeja ja Raamatun auktoriteettia vedotakseen kuulijoidensa kulttuurillisiin arvoihin? Aineiston prominentit retoriset keinot ovat toisto, kielikuvat, pronominien käyttö sekä pronominien suhde neuvojen ja käskyjen antamiseen. Tarkasteltavat kolme kulttuurista pääarvoa ovat individualismi, itsehoito sekä materialismi. Näiden …
Behavioral and Chemical Investigations of Contact Kairomones Released by the Mud Dauber Wasp Trypoxylon politum, a Host of the Parasitoid Melittobia …
2011
Contact kairomones from the host mud dauber wasp Trypoxylon politum Say (Hymenoptera: Crabronidae) that mediate behavioral responses of its ectoparasitoid Melittobia digitata Dahms (Hymenoptera: Eulophidae) were investigated. Chemical residues from host by-products, the cocoon, and the meconium, induced arrestment behavior of macropterous female parasitoids, while those from the host stage attacked, i.e., the prepupa, did not. Melittobia digitata response to polar and apolar extracts of host by-products indicated kairomone(s) solubility mainly in hexane. GC and GC/MS analysis of cocoon and meconium apolar extracts revealed a mixture of linear carboxylic acids from C(6) to C(18), and both ex…
Hard X-ray resonant electronic spectroscopy in transition metal oxides
2005
K-edge X-ray absorption and 2p-XPS spectra of 3d-element oxides present spectral features which cannot be explained within a simple one-electron model. These features reveal the fine electronic structure of transition metal (TM) oxides valence states resulting from hybridized TM-3d and O-2p states, and the correlations between these valence electrons. In this paper, we show how resonant electronic spectroscopy (resonant Auger or resonant photoelectron spectroscopy) around the TM K-edge can be used to interpret the structures of the threshold and, with the help of theoretical calculation, to determine the electronic configuration of the excited ion. Quadrupolar transitions towards localized …
Pokeri-ilta : etnografinen tutkimus rahapelaamisen yhteisöllisyydestä
2017
Tutkielmani tavoitteena on tutkia mitä merkityksiä opiskelijoiden pokeriyhteisö antaa yhteisölle ja pokeripelille: miksi he pelaavat pokeria ja minkä takia he viettävät aikaa yhteisössä? Peliyhteisön tutkimuksen pohjana käytän sosiologi Michel Maffesolin käsitettä uusheimolaisuus, johon sovellan ja vertaan tutkimaani yhteisöä. Lisäksi käyn läpi yhteisön jäsenten suhtautumista rahapelaamiseen ja erityisesti Texas Hold’em pokerivariaatioon, jota he yhteisössä pelasivat. Tutkimusmetodeina käytän teemahaastattelua sekä passiivista havainnointia ja osallistuvaa havainnointia. Tutkielmaani varten haastattelin viittä yhteisön jäsentä. Passiivista havainnointia yhteisössä toteutin kuukauden ajan ja…
Development and Implementation of the AIDA International Registry for Patients With VEXAS Syndrome
2022
ObjectiveThe aim of this paper is to present the AutoInflammatory Disease Alliance (AIDA) international Registry dedicated to Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic (VEXAS) syndrome, describing its design, construction, and modalities of dissemination.MethodsThis Registry is a clinical, physician-driven, population- and electronic-based instrument designed for the retrospective and prospective collection of real-life data. Data gathering is based on the Research Electronic Data Capture (REDCap) tool and is intended to obtain real-world evidence for daily patients' management. The Registry may potentially communicate with other on-line tools dedicated to VEXAS syndrome, thu…