| 1. |
- Bih, H., et al.
(författare)
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Pentaammonium heptasodium [bis(μ5-phosphato) pentakis (μ2-oxido)-decaoxidopentamolybdenum(VI)] henicosahydrate
- 2010
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Ingår i: Acta Crystallographica Section E. - 1600-5368. ; E66, s. 20-21
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Tidskriftsartikel (refereegranskat)abstract
- The title compound, (NH4)(5)Na-7[Mo5P2O23](2)center dot 21H(2)O, was prepared under atmospheric conditions in aqueous solution at room temperature. The structure contains the [Mo5P2O23](6-) heteropolyoxometallate anion, which has been previously reported a number of times with a variety of differing countercations. Each anion is built up of five MoO6 octahedra sharing an edge and forming a ring which is closed by common corners of the terminal octahedra. The rings are closed on both sides by two asymmetric PO4 tetrahedra, sharing three corners with three MoO6 octahedra. The anions are chiral and the two independent anions in the asymmetric unit were arbitarily chosen with the same chirality, but the centrosymmetric crystal contains both enantiomers. The structure can alternatively be described as a succession of layers parallel to (101), formed by the [Mo5P2O23](6-) anions and linked by sodium chains. Water molecules and ammonium ions fill the remaining space and ensure the cohesion through extensive N-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonding.
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| 2. |
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| 3. |
- Bih, H, et al.
(författare)
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Thermal and structural studies of Li2O-Na2O-SrO-TiO2-B2O3-P2O5 glasses by DTA, IR and EPR spectroscopy
- 2017
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Ingår i: Journal of Applied Surfaces and Interfaces. ; 1:1-3, s. 57-63
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Tidskriftsartikel (refereegranskat)abstract
- Glasses in the system 33.33[xNa2O-(1-x)Li2O]-2.5SrO-2.5TiO2-45B2O3-16.67P2O5 (0.0 ≤ x ≤ 1.0) were prepared by standard melt quenching procedures, and their physical properties were characterized by thermal analysis, density measurements. Their local structures were comprehensively characterized by Infrared spectroscopy (IR) and electron paramagnetic resonance (EPR). The variation of the glass transition temperature as a function of the glass compositions is non-linear. The infrared spectroscopy of the glasses has identified the presence of different structural grouping units in the glassy-matrix. It is found that the stretching and bending vibration modes of borate groups are more sensitive to the substitution of alkali elements. EPR experiments have shown the presence of Ti3+ centres in the glasses. The variation of the g-factor as a function of the Na/(Na+Li) ratio presents a minimum around (x=0.5). The composition non-linearity behavior of Tg, vibration bending mode, and g-factor are signature of the mixed alkali effect in the glasses.
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| 4. |
- Sartelli, Massimo, et al.
(författare)
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Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action
- 2023
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Ingår i: WORLD JOURNAL OF EMERGENCY SURGERY. - 1749-7922. ; 18:1
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Forskningsöversikt (refereegranskat)abstract
- Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or "golden rules," for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice.
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| 5. |
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| 6. |
- Azdouz, M, et al.
(författare)
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Synthesis, Rietveld refinements and Raman spectroscopy studies of the solid solution Na1-xKxPb4(VO4)(3) (0 <= x <= 1)
- 2010
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Ingår i: Journal of Molecular Structure. - : Elsevier BV. - 0022-2860 .- 1872-8014. ; 963:2-3, s. 258-266
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Tidskriftsartikel (refereegranskat)abstract
- In the present study we report the synthesis, crystal structure and Raman spectroscopy studies of Na1-xKxPb4(VO4)(3) orthovanaclates solid solutions (0 <= x <= 1). Rielveld refinements showed that this solid solution is continuous adopting P6(3)/m (no. 176) space group. Some of Pb(II) cations are located in the (6 h) sites. The ninefold coordination sites (4f) are equally occupied by the other lead cations and the K+ and Na+ monovalent ions. The structure can be described as built up from [VO4](3-) tetrahedral and Ph2+ of sixfold coordination cavities (6 h positions), which delimit void hexagonal tunnels running along [0 0 1]. These tunnels are connected by cations of mixed sites (4f) half occupied by Pb(II) and half by Na+/K+ mixed cations. The existence of this type of lacunar apatite seems to be conditioned by the presence of lone pair cations Pb(II). Raman spectra of all the compositions are similar and show some linear shifts in band positions as a function of the composition toward high values due the substitutions of Na+ by K+ with a larger radius. No considerable changes in the temperature dependence of the Raman modes and the corresponding FWHM are observed and thus no temperature induced phase transition is observed in Na0.5K0.5Pb4(VO4)(3) up to 650 K.
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| 7. |
- Bih, H., et al.
(författare)
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Electrical Transport Properties Of Iodine Oxide Phosphate Glasses Issued From The NaI-Li2O-WO3-P2O5 System
- 2010
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Ingår i: Moroccan Journal of Condensed Matter. - 1114-2073. ; 12, s. 98-102
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Tidskriftsartikel (refereegranskat)abstract
- Abstract: This work concerns the investigation of ion transport behaviour of NaI containing lithium tungstenphosphate glasses in order to understand better the role of NaI in the ionic cation transport. Glasses obtained in thesystem 0.5[x(2NaI)-(1-x)Li2O]-0.5[0.25(WO3)2-0.75P2O5] were investigated. The glass samples have beencharacterised using powder X-ray diffraction (XRD), thermal analysis, density and impedance spectroscopy. X-raydiffraction and thermal studies have confirmed that these glasses can be formed in the range x = 0 to 1. The mixedalkali glasses have shown higher activation energies and lower conductivities compared to single alkali doped glassesand this has been attributed to a mixed alkali effect.
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| 8. |
- Bih, H., et al.
(författare)
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Preparation and electrical conductivity of NaF-Li2O-WO3-P2O5 glasses
- 2009
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Ingår i: Journal of Optoelectronics and Advanced Materials. - 1454-4164 .- 1841-7132. ; 3:9, s. 959-963
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Tidskriftsartikel (refereegranskat)abstract
- Several studies have been reported on lithium phosphate glasses to which lithium halides and lithium sulphate have been added However, there has been no experimental results for the introduction of sodium fluoride into the lithium tungsten phosphate network How specifically this feature - mixed alkali in the presence of fluorine ion - influences ion transport in the glasses is unclear. This work concerns the investigation of ion transport behaviour of NaF containing lithium tungsten phosphate glasses in order to understand better the role of NaF in the ionic cation transport Glasses obtained in the system 0.5[x(2NaF)-(1-x)Li2O]-0.5[0.25(WO3)(2)-0.75P(2)O(5)] were investigated The glass samples have been characterised using powder X-ray diffraction (XRD), thermal analysis, density and impedance spectroscopy X-ray diffraction and thermal studies have confirmed that these glasses can be formed in the range x = 0 to 1 The mixed alkali glasses have shown higher activation energies and lower conductivities compared to single alkali doped glasses and this has been attributed to a mixed alkali influence on the electrical conduction in these systems.
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| 9. |
- Bih, H., et al.
(författare)
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Raman spectroscopic study of the phase transitions sequence in Li3Fe2(PO4)(3) and Na3Fe2(PO4)(3) at high temperature
- 2009
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Ingår i: Journal of Molecular Structure. - : Elsevier BV. - 0022-2860 .- 1872-8014. ; 936, s. 147-155
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Tidskriftsartikel (refereegranskat)abstract
- The phase transition properties of A3Fe2(PO4)3 (A = Li, Na) were studied by Raman spectroscopy. Several Raman bands change continuously in 25–400 °C temperature range, indicating a phase transition from the γ, β to the α-phase occurring at this range of temperature. Bands caused by vibrations of phosphate anion and different ions have been found. The spectra analysis reveals that the modes, located at low frequency range 100–400 cm−1, near 500 cm−1 at room temperature, are the most thermo-sensitive. In addition, the modes corresponding to bond valence stretching of (PO4) unit in the frequency region 970–1200 cm−1 show also evolution with temperature but less sensitive than the above ones. It is observed that phosphate groups show some ordering with temperature. According to our Raman study, we can state that each of the compounds LiFeP and NaFeP shows two reversible phase transformations in the temperature range studied.
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| 10. |
- Bih, H., et al.
(författare)
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X-ray diffraction and vibrational Raman spectra of the Li2-xNaxCo2(MO4)3 (0
- 2010
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Ingår i: Journal of Molecular Structure. - : Elsevier BV. - 0022-2860 .- 1872-8014. ; 965:1-3, s. 7-13
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Tidskriftsartikel (refereegranskat)abstract
- Synthesis, X-ray diffraction and Raman spectroscopy studies of Li2-xNaxCo2(MoO4) 3 (0 ≤ x ≤ 2) compositions have been investigated. These alkali-cobalt molybdates crystallize in the orthorhombic system (space group Pnma (D2h)) with a lyonsite structure (Z = 4). The cell parameters are determined by DICVOL04 software and confirmed by Rietveld refinements. The structure is formed by a framework of MoO4 tetrahedra and (Li/Na/Co)O6 octahedra, the tetrahedra provide links between sheets and columns formed by the octahedra. The structure shows that while octahedra share corners and edges in the sheets, they share faces columns. Alkali and cobalt are distributed statically in both the octahedral and trigonal prism sites. X-ray diffraction shows the presence of a solid solution in the range of compositions (0 ≤ x < 1.4). These results are in agreement with Raman studies where the spectra of all the compositions are similar and show linear shifts of the frequencies as a function of the composition toward low values due to the substitutions of Li+ by Na+ with a larger radius.
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