Search results for "Bismuth"
showing 10 items of 151 documents
The structural versatility of proton sponge bismuth halides
2022
Hybrid halometalates containing lead, tin, bismuth and antimony and organic cations have recently shown a bevy of interesting photophysical properties. Aiming at finding chemically stable and thermally inert species, three halobismutate species of this class, crystallized with proton sponge-derived cations (PRSH), have been isolated as microcrystalline powders by mixing 1,8-bis(dimethylamino)-naphthalene (proton sponge, or PRS) and bismuth oxide in concentrated HX acids (X = Cl, Br and I). The two isomorphous (PRSH)3Bi2X9 (X = Br, I) species, containing isolated [Bi2X9]3- anions, are triclinic at room temperature and convert upon heating into a monoclinic structure through a displacive …
Electrocaloric Effect in (1−x)(0.8Na0.5Bi0.5TiO3-0.2BaTiO3)−xCaTiO3 Solid Solutions at High Electric Fields
2022
This research was funded by the Latvian Science Council Fund, grant number lzp-2020/2-0080. The Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme, grant number 739508.
Arsenic, antimony and bismuth complexation by L-cysteine in water
1984
Synthese, dans l'eau, des complexes L-cysteine: AsL 3 , SbL 3 •H 2 O et BiL 3 .H 2 O L=forme monoanionique de cysteine. Etude IR des structures
Bismuth trihalide complexes with nitrogen and phosphorus chelating ligands
1985
Abstract Bismuth(III) halides react with 1,10-phenanthroline, 2-pyridinecarboxaldehyde-2-pyridylhydrazone and diphenylphosphynoethane in methanol. A stoichiometry differing from 1:1 is found only for BiCl 3 (Phen) 1.33 and BiCl 3 (Dpe) 1.5 . Characterization of these compounds, which are not very soluble in common solvents, follows from analytical, mass and IR spectral data. In the low frequency region, the IR spectra proved to be useful to ascertain the presence of bridging halogens.
Synthesis and characterization of some arsenic, antimony and bismuth complexes of 2-mercaptoaniline
1983
Abstract The complexes of arsenic, antimony and bismuth as well as phenylantimony and phenylbismuth with monoanionic 2-mercaptoaniline are reported. IR spectra are consistent with chelating behaviour of the ligand but only a weak nitrogen to metal bonding interaction is advanced. The mass spectra fragmentation pattern is also presented. It can be interpreted with the loss of successive ligand units and, as a general feature, the abundance of a given ion decreases as the mass of the metal increases. Species with one or two protons less give more intense peaks possibly corresponding to ions containing the dianionic form of the ligand.
A new 1-week therapy for Helicobacter pylori eradication: rani- tidine bismuth citrate plus two antibiotics
1997
Background: One-week triple regimens are currently the most recommended therapy for the eradication of Helicobacter pylori. No previous study has evaluated the efficacy of a short-term regimen combining ranitidine bismuth citrate with two antibiotics. Methods: Seventy-two consecutive H. pylori-positive dyspeptic patients were recruited for this randomized, three-centre, open, parallel-group study. They were subdivided into two groups receiving either ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. and metronidazole 500 mg b.d. (group A) or ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. and metronidazole 250 mg q.d.s (group B) for 1 week. H. pylori in…
Tuning the photocatalytic activity of bismuth wolframate: Towards selective oxidations for the biorefinery driven by solar-light
2017
The sol–gel entrapment of nanostructured Bi2WO6 enhances the activity and the selectivity of the short-gap semiconductor in the sunlight-driven photo-oxidation of trans-ferulic and trans-cinnamic acid dissolved in water with air as the primary oxidant. Valuable products such as vanillin, benzaldehyde, benzoic acid and vanillic acid are obtained. This provides the proof of concept that photocatalysis could be a promising technology in tomorrow's solar biorefineries.
Spectral properties and lifetime of green emission in γ-ray irradiated bismuth-doped silica photonic crystal fibers
2018
Abstract We report an experimental investigation focused on the green emission detected in γ-ray irradiated Bismuth-doped photonic crystal fibers. Our photoluminescence spectra, recorded at room temperature, provide evidence for the presence of two emission bands both located at ~ 530 nm (2.34 eV). One emission is detected only in the Bi-doped core while the other, is detected in the cladding. These two emissions feature different excitation spectra and a fast and a slow decay lifetime. The origin of the fast emission decay, about ten nanoseconds, is tentatively attributed to a silica intrinsic defect, whereas the slow component, having lifetime of about 2 μs and featuring anti-stokes emiss…
A comparative study of photocatalytically active nanocrystalline tetragonal T zyrcon- type and monoclinic scheelite-type bismuth vanadate
2018
The authors from Vinča Institute of Nuclear Sciences acknowledge the financial support of the Ministry of Education, Science and Technological Development of the Republic of Serbia (Project no: 172056 ). The work of K. Smits was supported by Latvian National Research Program IMIS2 (Grant no. 302/2012 ).
The Influence of Morphological Aspects in the Reaction Pathway and Superconductive Properties of Bi2223-Ca2CuO3 Ceramic Composites
1994
ABSTRACTA variation of the solid-state matrix technique has been developed as a procedure for the preparation of 2223 bismuth superconducting phases [(Bi,Pb)2Sr2Ca1-nCunO4+2n, n=3]. The adequate processing of samples of nominal compositions 2223+x 0021, obtained both by this procedure and by the polymer matrix method, has allowed the modification of the microstructure of the calcium copper excess, with no noticeable change in that of the 2223 grains. The study of the phase evolution in the processing of the samples has shown that the formation rate of the 2223 phase is faster when the particle size of the calcium cuprate is smaller. A dependence of the intergranular superconducting properti…