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Characterization of silica supported chromium complexes
(Planta Piloto de Ingeniería Química, 2000-03)
The Cr/SiO2 catalysts were prepared via the deposition of mononuclear and binuclear chromium (III) ammine complexes on silica. The influence of chromium loading and calcination temperatura upon the type of species formed ...
Tris(pyrazolyl)methane-chromium(III) complexes as highly active catalysts for ethylene polymerization
(ELSEVIER SCIENCE BV, 2006)
Reaction of complex CrCl3 (THF)(3) with the tris(pyrazolyl)methane ligands, HC(Pz)(3), HC(3,5-Me(2)Pz)(3) and their substituted derivatives RC(Pz)(3) (R = Me, CH2OH, CH2OSO2Me) in THF lead to the formation of neutral ...
Preconcentration and speciation of Cr(III) and Cr(VI) in water samples using amberlite XAD-16 resin and determination by flow injection-flame AAS
(Perkin-Elmer Corporation, 2002-03)
A method for the pre-concentration and speciation of chromium was developed. On-line pre-concentration and determination were obtained using flame atomic absorption spectrometry (FAAS) coupled with flow injection (FI). To ...
Band shift in chromium(III) complexes with mixed ligands: molecular orbital approach
(Pergamon Press, 1969)
The shift of the first and second spin allowed bands due to the stepwise replacement of the nitrogen atoms in a complex of Cr(III) of the CrN6 type of oxigen atoms of water or of carboxylic groups is analized in terms of ...
Distribution and bioavailability of chromium in contaminated soils by tannery residuesDistribuição e biodisponibilidade de crómio em solos contaminados por resíduos de couro
(2009-01-01)
Samples of soil, water and sediment were collected and analyzed in order to evaluate chromium, contamination due to deposition of tannery residues onto soils under different management regimes. The results showed that soils ...
New bis(azolylcarbonyl)pyridine chromium(III) complexes as initiators for ethylene polymerization
(ELSEVIER SCIENCE SA, 2011)
Reaction of 2,6-pyridinedicarbonyl dichloride with 3,5-dimethylpyrazole and 1H-indazole, respectively, yield the tridentate ligands 2,6-bis(3,5-dimethylpyrazol-1-ylcarbonyl)pyridine (1) and 2,6-bis(indazol-1-ylcarbonyl)pyridine ...
Synthesis, crystal structure, catalytic and anti-Trypanosoma cruzi activity of a new chromium(III) complex containing bis(3,5-dimethylpyrazol-1-yl)methane
(Journal of Molecular Structure, 2019)