Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add more filters










Database
Language
Publication year range
1.
Chaos ; 27(8): 083111, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28863479

ABSTRACT

Metal electrodeposition systems display tree-like structures with extensive ramification and a fractal character. Electrolysis is not a necessary route for the growth of such dendritic metal deposits. We can grow beautiful ramification patterns via a simple redox reaction. We present here a study of silver (Ag) deposits from the reduction of Ag+ in (AgNO3) solution by metallic copper. The experiments are carried out in discotic geometry, in a Petri dish hosting a thin AgNO3 solution film. A variety of deposited structures and patterns is obtained at different Ag+ concentrations, yet with essentially the same fractal dimension averaged at 1.64, typical of diffusion-limited aggregation (DLA). A linear magnetic field of low induction (0.50-1.0 T) applied across the medium causes a notable transformation in the morphology of the deposits. In both the field off and the field on cases, the effect of vertical (hence 3D) heaving seems to be dominant, perhaps explaining the nearly constant fractal dimension.

2.
Chem Biol Interact ; 231: 53-60, 2015 Apr 25.
Article in English | MEDLINE | ID: mdl-25753321

ABSTRACT

The dinuclear complex bis[(µ(2)-chloro)chloro(1,10-phenanthroline)copper(II)] (1) was synthesized, and characterized by X-ray, FTIR and thermal analysis. The fitting of magnetic susceptibility and magnetization curve of (1) indicates the occurrence of weak antiferromagnetic exchange interaction between copper(II) ions. The electronic structure has been also determined by density functional theory (DFT) method. Complex (1) displayed potent anticancer activity against B16 (Melanoma), MDA-MB-32 (Breast Adenocarcinoma), A549 (Lung Adenocarcinoma), HT-29 (Colon Adenocarcinoma) and SF (Astrocytoma) cell lines with an average IC50 value of 0.726 µg/ml compared to 4.88 µg/ml for cisplatin. Complex (1) has a better therapeutic index and toxicological profile than cisplatin, and has demonstrated a potential chemotherapeutic property.


Subject(s)
Antineoplastic Agents/chemistry , Coordination Complexes/chemistry , Copper/chemistry , Phenanthrolines/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Coordination Complexes/pharmacology , Copper/pharmacology , Crystallography, X-Ray , Halogenation , Humans , Magnetic Phenomena , Models, Molecular , Neoplasms/drug therapy , Phenanthrolines/pharmacology
3.
Inorg Chem ; 38(16): 3670-3675, 1999 Aug 09.
Article in English | MEDLINE | ID: mdl-11671124

ABSTRACT

The novel dimeric polyoxometalate [{beta-SiNi(2)W(10)O(36)(OH)(2)(H(2)O)}(2)](12)(-) (1) has been synthesized and characterized by IR spectroscopy, polarography, elemental analysis, thermogravimetric analysis, and magnetic measurements. An X-ray single-crystal analysis was carried out on K(12)[{beta-SiNi(2)W(10)O(36)(OH)(2)(H(2)O)}(2)].20H(2)O, which crystallizes in the monoclinic system, space group P2(1)/n, with a = 13.701(4) Å, b = 24.448(11) Å, c = 13.995(5) Å, beta = 99.62(3) degrees, and Z = 4. The anion consists of two [beta-SiNi(2)W(10)O(36)(OH)(2)(H(2)O)] Keggin moieties linked via two OH bridging groups, leading to a planar Ni(2)(OH)(2) unit. The two half-units are related by an inversion center and each contain one Ni atom in the rotated triad. The formation of the new anion involves insertion, isomerization, and dimerization. Magnetic measurements show that the central Ni(4) unit exhibits ferromagnetic (J' = 4.14 cm(-)(1)) as well as weak antiferromagnetic (J = -0.65 cm(-)(1)) Ni-Ni exchange interactions.

SELECTION OF CITATIONS
SEARCH DETAIL
...