Metal Complexes
Mostrando 13-24 de 472 artigos, teses e dissertações.
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13. ESPECIAÇÃO DINÂMICA DE METAIS TRAÇO EM AMBIENTE AQUÁTICO USANDO CRONOPOTENCIOMETRIA DE REDISSOLUÇÃO ANÓDICA
The contamination of natural environments by trace metals has several adverse effects on human health, which is mainly due to the high toxicity, persistence and reactivity of these species in the environment. To understand the bioavailability of trace metals, it is necessary to know the speciation in equilibrium and the dynamic behavior of the system. In thi
Quím. Nova. Publicado em: 2018-07
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14. Structure/Activity of PtII/N,N-Disubstituted-N'-acylthiourea Complexes: Anti-Tumor and Anti-Mycobacterium tuberculosis Activities
The syntheses, characterization, cytotoxicity against tumor cells and anti-Mycobacterium tuberculosis activity assays of PtII/PPh3/N,N-disubstituted-N'-acylthioureas complexes with general formulae [Pt(PPh3)2(L)]PF6, PPh3 = triphenylphosphine; L = N,N-disubstituted-N'-acylthiourea, are here reported. The complexes were characterized by elemental analysis, mo
J. Braz. Chem. Soc.. Publicado em: 2018-06
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15. AVALIAÇÃO DOS RESÍDUOS GERADOS DURANTE A DESTRUIÇÃO DE PCBS PELO PROCESSO CATALISADO POR BASE
There are many processes capable of decontamination of polychlorinated biphenyls in several matrixes. The set of inputs, materials, operation conditions and efficiencies are wide. The base catalyzed dechlorination process shows application potential in great scale, mainly due mild chemical reaction conditions and low cost raw materials. The KPEG is a familia
Quím. Nova. Publicado em: 2018-06
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16. New Organomineral Complex from Humic Substances Extracted from Poultry Wastes: Synthesis, Characterization and Controlled Release Study
The present study reports the synthesis and characterization of complexes formed among humic (HA) and fulvic acids (FA) derived from poultry wastes and ions Cu2+, Fe2+ and Zn2+. The release of such metals in a buffer solution simulating the soil solution was also evaluated. After complexation, the Fourier transform infrared (FTIR) spectra presented alteratio
J. Braz. Chem. Soc.. Publicado em: 2018-01
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17. The role of condensed tannins in ruminant animal production: advances, limitations and future directions
ABSTRACT Tannins represent one of the most abundant polyphenolic compounds in plants. Tannins exist as a multitude of chemically unique entities in nature. The most commonly occurring tannins are typically divided into two major classes based on chemical structure: hydrolysable (HT) or condensed tannins (CT). Hydrolysable tannins are esters of gallic or ella
R. Bras. Zootec.. Publicado em: 2017-12
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18. Cellulose Oxidation and the Use of Carboxyl Cellulose Metal Complexes in Heterogeneous Catalytic Systems to Promote Suzuki-Miyaura Coupling and C-O Bond Formation Reaction
This work shows the modification of microcrystalline cellulose by the selective oxidation of primary hydroxyl groups to carboxylate groups by a 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated system and its application as a heterogeneous ligand by ionic exchange with catalytic metals ions such as palladium, nickel and copper. Afterwards is desc
J. Braz. Chem. Soc.. Publicado em: 2017-11
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19. Polypyridyl Ruthenium Complexes: Novel DNA-Intercalating Agents against Human Breast Tumor
This paper describes a new series of four DNA-intercalating agents with promising anticancer activities, based on ruthenium(II) with the planar ligand dpqQX (dpqQX = dipyrido[3,2-a:2',3'-c]quinoxaline[2,3-b]quinoxaline). The complexes identified as trans-[RuCl2(dppb)(dpqQX)], cis-[RuCl2(dppb)(dpqQX)], ct-[RuCl(CO)(dppb)(dpqQX)]PF6 and ct-[RuCl2(PPh3)2(dpqQX)
J. Braz. Chem. Soc.. Publicado em: 2017-10
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20. Influence of the Protonatable Site in the Photo-Induced Proton-Coupled Electron Transfer between Rhenium(I) Polypyridyl Complexes and Hydroquinone
In the present work the influence of the distance of the protonatable site of different ancillary ligands to the metal center on the luminescence quenching of ReI polypyridyl complexes by hydroquinone are evaluated by means of experimental and theoretical studies. In these systems, it is expected the occurrence of proton-coupled electron transfer (PCET) reac
J. Braz. Chem. Soc.. Publicado em: 2017-09
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21. Catechol Oxidase, Phosphatase-Like Activity, DNA/BSA Binding Studies of RuII Complexes of S-Allyldithiocarbazate: Synthesis and Spectral Studies
New ruthenium(II) complexes with formulae [RuCl(CO)(PPh3)2L1] and [RuCl(CO)(PPh3)2L2] (L1 = S-allyl-4-methoxy benzylidene hydrazine carbodithioate, L2 = S-allyl-1-naphthylidene hydrazine carbodithioate) have been synthesized and characterized by elemental analysis, Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), UV-Vis, electrospray ioni
J. Braz. Chem. Soc.. Publicado em: 2017-08
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22. Copper II - polar amino acid complexes: toxicity to bacteria and larvae of Aedes aegypti
ABSTRACT Control strategies using insecticides are sometimes ineffective due to the resistance of the insect vectors.In this scenario new products must be proposed for the control of insect vectors.The complexes L-aspartate Cu (II) and L-glutamate-Cu (II) complexes were synthesized and characterized by elemental analysis, visible ultraviolet, infrared spectr
An. Acad. Bras. Ciênc.. Publicado em: 20/07/2017
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23. Endophytic fungus Purpureocillium sp. A5 protect mangrove plant Kandelia candel under copper stress
Abstract Mangrove is an important ecosystem in the world. Mangrove ecosystems have a large capacity in retaining heavy metals, and now they are usually considered as sinks for heavy metals. However, the mechanism of why the soil of mangrove ecosystems can retain heavy metal is not certain. In this research, endophytic fungus Purpureocillium sp. A5 was isolat
Braz. J. Microbiol.. Publicado em: 2017-07
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24. Synthesis, Characterization and Antimicrobial Activities of Copper, Nickel, Cobalt, Chromium Complexes Derived from (Z)-4-Fluoro-N-(2,7-dimethylhept-6-enylidene) benzenamine
Melonal is a relatively unexplored ingredient in the field of chemistry with excellent sensory properties. The synthesis and characterization of novel transition 3d metal complexes of copper(II), nickel(II), cobalt(II) and chromium(III) involving the Schiff base of melonal were explored to examine their biological activity. Characterization of the complexes
J. Braz. Chem. Soc.. Publicado em: 2017-05