Search results for "antimony"
showing 10 items of 163 documents
Structural and vibrational study of cubic Sb2O3under high pressure
2012
We report an experimental and theoretical study of antimony oxide (Sb${}_{2}$O${}_{3}$) in its cubic phase (senarmontite) under high pressure. X-ray diffraction and Raman scattering measurements up to 18 and 25 GPa, respectively, have been complemented with ab initio total-energy and lattice-dynamics calculations. X-ray diffraction measurements do not provide evidence of a space-group symmetry change in senarmontite up to 18 GPa. However, Raman scattering measurements evidence changes in the pressure coefficients of the Raman mode frequencies at 3.5 and 10 GPa, respectively. The behavior of the Raman modes with increasing pressure up to 25 GPa is fully reproduced by the lattice-dynamics cal…
Synthesis and Characterization of Lead-Free (1-x)(K0.5Na0.5)Nb1-ySbyO3-xBaTiO3
2011
In this study lead-free ceramics with a formula (1-x)(K0.5Na0.5)Nb1-ySbyO3-xBaTiO3 have been synthesized and studied. XRD studies showed that all compositions have perovskite structure with monoclinic or tetragonal cell depending on substitution level. KNN ceramics with BaTiO3 have more homogeneous structure and increased density in comparison with pure KNN or antimony substituted KNN. Dielectric measurements revealed diffuse phase transition.
Inorganic geochemistry of roadway dust from the metropolitan area of Palermo, Italy
2003
Inorganic matter from roadway dust collected in the urban area of Palermo, Italy, was analysed to identify the chemical elements introduced into the environment as a result of human activities. Metals of environmental concern exhibit very high enrichment factors, which in some cases exceed 100. Metal size distribution indicates that Pd, Pt, Au, Sb, Zn, S, Ni, V, Mo and Cr substantially accumulate in the finest particles, whereas Pb, Br, As, Cu, Ag and Ba are almost independent of the size fraction. SEM/EDS analyses revealed that some individual particles contain clusters of foreign particles (<10 μm) made up of Fe-Ni, Cr-Ni or Fe alone, typical of the abrasion of stainless steel. Others are…
Use of lichens in detecting environmental risk and in geochemical prospecting
1995
This paper provides data on variations in the contents of As, Sb, Ni, V, Pb, Cu, Cr, Au, Zn, Sc, and Al, measured in the thalli of a saxicolous lichen species,Xanthoria calcicola Ochsner s.l., collected in northeastern Sicily, near an industrial zone and along a belt crossing areas of known ores containing sulfides of heavy metals. A total of 91 lichen samples were collected on roof tiles (39) and on rocks (52). In the industrial zone, analysis of lichen thalli revealed high contents of nickel and vanadium, decreasing at increasing distances from the source of contamination. The results have also revealed the versatility ofXanthoria calcicola in geochemical prospecting for heavy metals such…
Complexes of dichlorophenyl and trichloro-antimony(V) moieties with dianionic tridentate ligands
1981
Broadband Dielectric Investigation of Sodium Potassium Niobate Ceramic Doped 8% of Antimony
2012
In this work we present dielectric permittivity measurement results of KNN ceramic doped antimony (K0.5Na0.5)(Nb0.92Sb0.08)O3 with sintering aid MnO2 (0.5 mol% MnO2) (KNNSbx + 0.5Mn). Its dielectric properties were investigated in broad frequency (from 20 Hz to 32 GHz) and temperature (from 26 K to 780K) ranges. Above room temperature obtained results show two diffused phase transitions. Below room temperature investigation revealed dielectric permittivity dispersion similar to the relaxor one. The obtained mean relaxation times fulfills Arrhenius relationship with dipole activation energy Ea/kB = 2282 K.
Control of matrix interferences by the multiple linear regression model in the determination of arsenic, antimony and tin in lead pellets by inductiv…
2002
A multiple linear regression technique was used to evaluate the matrix interferences in the determination of hydride-forming elements in lead shotgun pellets by inductively coupled plasma atomic emission spectrometry. The determination of arsenic, antimony, and tin in SRM C2416 (Bullet Lead) by ICP-AES failed to obtain the certified concentrations at the 95% level of confidence using the t-test. However, it proved possible, by using the multiple linear regression technique, to correct the concentrations of all three elements to a statistically acceptable level. This method of correction is based on the multiple regression line obtained from the analysis of 19 synthetic mixtures of matrix el…
Investigations on organoantimony compounds XI. Triorganoantimony(V) compounds containing potentially tridentate ligands
1974
Triorganoantimony(V) compounds of the types RSbVL, in which R = Me or Ph, and L represents a potentially tridentate dianionic Schiff base ligand of the ONO or SNO type, have been synthesized and investigated by spectroscopic (UV, IR, PMR) methods. Molecular weight determinations in benzene reveal the monomeric nature of these compounds. The free ligands, HL, used in this study are:,′-(methylidynenitrilo)diphenol (HSab), -(o-hydroxyphenyl)benzothiazoline (H-Sat), -(o_hydroxyanilino)crotonophenone (HBah), 4-(o-hydroxyphenylimino)--pentanone (HAah) and -acetonyl--methylbenzothiazoline (HAat). Both the UV and the IR data suggest hexacoordinate molecular structures for the complexes RSbL in whic…
CCDC 2063254: Experimental Crystal Structure Determination
2021
Related Article: Ying Kai Loh, Petra Vasko, Caitil��n McManus, Andreas Heilmann, William K. Myers, Simon Aldridge|2021|Nat.Commun.|12|7052|doi:10.1038/s41467-021-27104-y
CCDC 863728: Experimental Crystal Structure Determination
2013
Related Article: G.A.Horley, G.Kociok-Kohn, K.C.Molloy, J.R.Castro, S.Morreale|2012|Z.Anorg.Allg.Chem.|638|1699|doi:10.1002/zaac.201200024