Impact of the annealing temperature on Pt/g-C3N4 structure, activity and selectivity between photodegradation and water splitting

Acknowledgements: The authors would like to thank SABIC as well as EPSRC platform grant [EP/K015540/1] for financial support and the Royal Society of Chemistry for a Wolfson Merit Award. In order to protect intellectual property the data underpinning this publication are not made publicly available. All enquiries about the data should be addressed to [email protected] reviewedPostprin

Plasmonic-Assisted Water–Gas Shift Reaction of Gold Particles on TiO₂

The Localized Surface Plasmon (LSP) effect of 5 nm mean size Au particles deposited on TiO2 P25 was investigated during the photo-thermal water gas shift reaction (WGSR). The effects of CO concentration, excitation light flux and energy, and molecular oxygen addition during the reaction were investigated. The photocatalytic WGSR rate under light excitation with wavelengths extending from 320 to 1100 nm was found to be higher than the thermal reaction alone at the same temperature (85 °C). A H2/CO2 ratio of near unity was found at high concentrations of CO. The addition of molecular oxygen during the reaction resulted in a slight decrease in molecular hydrogen production, while the rates of CO2 formation and CO consumption changed by one order of magnitude. More importantly, it was found that the WGSR rates were still high under only visible light excitation (600–700 nm). The results prove that Au LSP alone triggers this chemical reaction without requiring the excitation of the semiconductor on which they are deposited

Syndrome de Marcus-Gunn: à propos d'un cas

Le syndrome de Marcus Gunn est un syndrome qui associe un ptosis congénital et une syncinésie mandibulo-palpébrale lors de certains mouvements mandibulaires. Nous rapportons le cas d'un enfant de quatre ans et demi qui présente un ptosis de la paupière gauche qui disparait lors de l'ouverture buccale. L'examen montre une acuité visuelle de 4/10 ème un ptosis majeur associée à une hyperaction du muscle frontal. L'examen somatique est sans particularités. L'enfant a bénéficié d'une section du muscle releveur supérieur avec une suspension frontale suivie d'une correction optique totale et d'un traitement de l'amblyopie. Pan African Medical Journal 2016; 2

Identification of Intermediates in the Reaction Pathway of SO2_{2} on the CaO Surface: From Physisorption to Sulfite to Sulfate

The interaction of CaO and Ca(OH)$_{2}$ with solvated or gaseous SO$_{2}$ plays a crucial role in the corrosion of urban infrastructure by acid rain or in the removal of SO$_{2}$ from flue gas. We carried out a combined spectroscopic and theoretical investigation on the interaction of SO$_{2}$ with a CaO(001) single crystal. First, the surface chemistry of SO$_{2}$ was investigated at different temperatures using polarization-resolved IR reflection absorption spectroscopy. Three species were identified, and an in-depth density functional theory study was carried out, which allowed deriving a consistent picture. Unexpectedly, low temperature exposure to SO$_{2}$ solely yields a physisorbed species. Only above 100 K, the transformation of this weakly bound adsorbate first to a chemisorbed sulfite and then to a sulfate occurs, effectively passivatating the surface. Our results provide the basis for more efficient strategies in corrosion protection of urban infrastructure and in lime-based desulfurization of flue gas

Heterogenized water oxidation catalysts prepared by immobilizing Klaui-type organometallic precursors

An efficient heterogenized water oxidation catalyst (2_TiO2) has been synthesized by immobilizing the Kläui-type organometallic precursor [Cp*Ir{P(O)(OH)2}3]Na (2, Cp*=1,2,3,4,5-pentamethylcyclopentadienyl ligand) onto rutile TiO2. Iridium is homogeneously distributed at the molecular and atomic/small cluster level in 2_TiO2 and 2'_TiO2 (solid catalyst recovered after the first catalytic run), respectively, as indicated by STEM-HAADF (scanning transmission electron microscopy - high angle annular dark field) studies. 2'_TiO2 exhibits TOF values up to 23.7 min-1 in the oxidation of water to O2 driven by NaIO4 at nearly neutral pH, and a TON only limited by the amount of NaIO4 used, as indicated by multiple run experiments. Furthermore, while roughly 40¿% leaching is observed during the first catalytic run, 2'_TiO2 does not undergo any further leaching even when in contact with strongly basic solutions and completely maintains its activity for thousands of cycles. NMR studies, in combination with ICP-OES (inductively coupled plasma optical emission spectrometry), indicate that the activation of 2_TiO2 occurs through the initial oxidative dissociation of PO43-, ultimately leading to active centers in which a 1:1 P/Ir ratio is present (derived from the removal of two PO43- units) likely missing the Cp* ligand.Peer ReviewedPostprint (author's final draft

Up-conversion luminescence coupled to plasmonic gold nanorods for light harvesting and hydrogen production

The conversion of infrared light to visible-light which allows a larger fraction of sun-light to be used is needed to improve light-harvesting. In this work a tri-functional material composed of an up-converter (NaYF4–Yb–Tm), plasmonic gold nanorods and CdS was made photocatalytically active using 980 nm wavelength light for the reduction of H+ to H2.Peer ReviewedPostprint (author's final draft

Tuberculose orbitaire: à propos d’un cas

La tuberculose sévit à l'état endémique au Maroc, l'atteinte orbitaire est rare et peut se faire par voie hématogène ou par contigüité à partir d'un foyer de voisinage. Nous rapportons le cas d'une patiente de 42 ans qui présente une exophtalmie droite dont l'enquête étiologique révèle une tuberculose orbitaire.Key words: Tuberculose, orbite, exophtalmi

Occult hepatitis B virus infection in Moroccan HIV infected patients

Background: The purpose of this study is to assess the prevalence of Occult hepatitis B virus Infection (OBI) among antiretroviral treatment naïve HIV-1 infected individuals in Morocco and to determine factors favouring its occurrence.Methods: The retrospective study was conducted in the Mohammed V military teaching hospital in Rabat between January 2010 and June 2011. It included patients with confirmed HIV infection, tested negative to serological detection of HBV surface antigen (HBsAg) and did not received antiviral treatment or hepatitis B vaccine. All samples were tested for anti-HBc, anti-HBs and anti-HCV antibodies using enzyme immunoassay (ELISA). The detection of HBV DNA was performed by real-time PCR using two specific primers for a gene in the region C of the viral genome. The sensitivity of the technique was 20 copies/ml.Results: A total of 82 samples were analyzed, 19 (23 %) were found to have isolated anti-HBc, 07 (8.5%) with associated anti-HBc and Anti-HBs. No anti-HCV marker was detected on these screening samples. The HBV DNA was detected in 48 (58%) samples, of which, males constituted 58% (28/48). The mean age of these patients was 38 ± 8.2 (29-56), the median HIV-1 viral load and CD4 cell count HIV-1 infected patients were 127500 (54108-325325) copies/ml and 243 [80-385] cells/mm3 respectively and 27.1% (13/48) of these patients were found to have isolated anti-HBc. A significant correlations between DNA HBV and HIV viral load higher than 100000 copies/ml (P = 0.004), CD4 cell count lower than 400 cells/mm3 (P = 0.013, P = 0.006) and isolated anti-HBc samples (P <0.005) were founded. However there was no significant association with age, sex, transmission mode and clinical stage.  Conclusion: The consequences of this high prevalence of OBI in Morocco need to be considered in laboratory diagnosis of HBV infection in HIV infected patients and the PCR seems to be inevitable for a better diagnosis and therapy.