Search results for "Bromide"
showing 10 items of 591 documents
Paper Functionalized with Nanostructured TiO2/AgBr: Photocatalytic Degradation of 2–Propanol under Solar Light Irradiation and Antibacterial Activity
2020
A facile method to produce paper&ndash
Ultrathin lead bromide perovskite platelets spotted with europium(ii) bromide dots
2019
We describe here the preparation of a novel nanohybrid comprising a two-layer cesium lead bromide nanoplatelet, [CsPbBr3]PbBr4 NPL, containing europium(II) bromide (EuBr2) nanodots, by ultrasound/heating treatment of toluene dispersions of the CsPbBr3 nanomaterial in the presence of EuBr2 nanodots. The hybrid nanoplatelets exhibit strong excitonic and narrow emission peaks characteristic of ultrathin NPLs at 430 and 436 nm, respectively.
Synthesis and characterization of mesoporous Mn-MCM-41 materials
2011
Si { 1 H} CP-MAS NMR X-ray photo-emission spectroscopy a b s t r a c t MCM-41 has been synthesized at two different pH using cetyl-trimethylammonium bromide (CTAB) surfactant as template and adding the silica precursor to aqueous solutions containing CTAB. The obtained solids were calcined at 600 ◦ C for 4 h. Mn-MCM-41 powders with different Mn/Si molar ratios were prepared using the incipient wetness method, followed by calcination at 550 ◦C for 5 h. At the end of the impregnation process the powders colour changed from white to brown whose intensity depends on manganese quantity. The materials characterization was performed by X-ray diffraction, N2 adsorption, 29 Si Cross Polarization–Mag…
One-pot synthesis and characterization of aliphatic poly(oxytetramethylene) ionene
2002
Abstract One-pot synthesis of poly(oxytetramethylene) ionene (POI) composed of one dimethylammonium group in each repeating unit is described. POI was prepared by using the cationic polymerization of tetrahydrofuran, followed by the chain extension reaction of living poly(oxytetramethylene) (POTM) chain with N , N -dimethylaminotrimethylsilane. The weight average molecular weight of the ionene with bromide counter-anion (POI–Br) was 48,000 g/mol and the molecular weight of POTM between the ionic sites was ca. 2100. POI–Br showed polyelectrolyte behavior in polar solvent. The elastomeric film of POI–Br was prepared: its tensile strength at break and elongation at break were ca. 11 MPa and ca…
Nano-composite thermochromic thin films and their application in Energy-efficient glazing
2010
A hybrid atmospheric pressure and aerosol-assisted chemical vapour deposition strategy is presented as a facile route for the production of vanadium dioxide nano-composite thin films. The effect of the inclusion of gold nanoparticles and the use of a surfactant molecule, tetraoctylammonium bromide, is discussed. The films were fully characterised using a wide variety of techniques, including scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and UV/vis/NIR spectroscopy. It is shown that micro-structural changes brought about by careful control of film growth conditions, and/or the use of surfactant, lead to an enhancement of thermochromic properties. Gold nano…
The Antimicrobial Action of Silver Halides in Calcium Phosphate
2014
Silver halides represent a yet unexplored avenue for imparting antimicrobial activity to calcium phosphates. Negtively charged silver halide colloids (AgI, AgBr and AgCl) were added to synthesized amorphous calcium phosphate. Concurrent melting of silver halides and crystallization to carbonated apatite at 700 oC increased the silver halide surface area available to bacteria and formed a lower solubility apatite. The effect of the matrix solubility on antimicrobial response could then be investigated. Pseudomonas aeruginosa was more sensitive to silver iodide and silver bromide than Staphylococcus aureus. Silver iodide demonstrated greater activity than silver bromide. Silver chloride did n…
Bamboo-like Chained Cavities and Other Halogen-Bonded Complexes from Tetrahaloethynyl Cavitands with Simple Ditopic Halogen Bond Acceptors
2018
Halogen bonding provides a useful complement to hydrogen bonding and metal-coordination as a tool for organizing supramolecular systems. Resorcinarenes, tetrameric bowl-shaped cavitands, have been previously shown to function as efficient scaffolds for generating dimeric capsules in both solution and solid-phase, and complicated one-, two-, and three-dimensional frameworks in the solid phase. Tetrahaloethynyl resorcinarenes (bromide and iodide) position the halogen atoms in a very promising “crown-like” orientation for acting as organizing halogen-bond donors to help build capsules and higher-order networks. Symmetric divalent halogen bond acceptors including bipyridines, 1,4-dioxane, and 1…
Magnetic Langmuir–Blodgett films of ferritin with different iron loadings
2005
Abstract Magnetic Langmuir–Blodgett multilayers of two ferritin molecules 1 and 2 , containing, respectively, 4220 and 3062 Fe atoms have been prepared by using the adsorption properties of a 6/1 mixed monolayer of dioctadecyldimethylammonium bromide (DODABr) and methyl stearate (SME). Transfer ratios close to unity were reached giving rise to LB films with a strong red colour. Infrared and UV–vis spectroscopy indicates that ferritin molecules are incorporated within the LB films. Magnetic measurements show that the superparamagnetic properties of these molecules are preserved. Thus, a marked hysteresis loop of magnetisation is obtained for LB films of 1 and 2 with a coercive field of 3400 …
The ‘Irving–Williams’ Order in the Metal-ligand Stretching Frequencies of Some Metal Hydrazine Complexes
1960
MANY infra-red spectra of metal complexes have been examined in the 2–15μ region, but until now very few co-ordination compounds have been studied in the caesium bromide region in which some metal-ligand atom-stretching frequencies are expected1. Furthermore, no correlation between the frequency of this vibration and the nature of the metal has been found2.
Poly[[μ-N,N′-bis(2-hydroxyethyl)-N,N,N′,N′-tetramethylpropane-1,3-diaminium-κ2O:O′]tetra-μ-bromido-dibromidodimanganese(II)]
2012
The asymmetric unit of the title three-dimensional coordination polymer, [Mn2Br6(C11H28N2O2)] n , consists of one Mn(II) cation, half of a dicationic N,N'-bis-(2-hy-droxy-eth-yl)-N,N,N',N'-tetra-methyl-propane-1,3-diaminium ligand (L) (the other half being generated by a twofold rotation axis), and three bromide ions. The Mn(II) cation is coordinated by a single L ligand via the hy-droxy O atom and by five bromide ions, resulting in a distorted octa-hedral MnBr5O coordination geometry. Four of the bromide ions are bridging to two adjacent Mn(II) atoms, thereby forming polymeric chains along the a and b axes. The L units act as links between neighbouring Mn-(μ-Br)2-Mn chains, also forming a …