Search results for "Nickel ion"
showing 4 items of 4 documents
Quantitative and Qualitative in vivo Analysis of Metal Residuals in the Saliva of Subjects with and without Fixed Orthodontic Appliances
2020
Aim of the Work: The aim of this work was to evaluate Ni e Cr ions in the saliva of subjects with and without fixed orthodontic appliances. Materials and Methods: This was a prospective, non-randomized study of 100 patients, so selected: 50 have undergone fixed orthodontic appliance at least from 24 months; others 50 subjects as control-group, without any fixed and/or removable orthodontic appliance It was conducted according to the Declaration of the World Medical Association of Helsinki. The two selected groups were compatible for age, sex, absence of restoration in amalgam or other metals in the oral cavity. The saliva of all the subjects was collected with standardized sterile methods. …
Host molecules containing electroactive cavities obtained by the molecular assembly of redox-active ligands and metal ions
1995
Self-assembly processes of nickel ions with the redox-active ligand 1,4,8,11-tetra(ferrocenylmethyl)-1,4,8,11-tetraazacyclotetradecane (Fc4cyclam) induces the formation of a redox-active cavity of potential use in electrocatalysis.
Hardening in LiF induced by fast Ni ions and recovery of properties under annealing
2005
The recovery of hardness and optical absorbance of LiF crystals irradiated with 640 MeV nickel ions under annealing at 450–810 K is investigated. Recovery of the hardness of irradiated crystals is initiated at temperatures above 530 K, at which a transition from a complex absorption spectrum to a spectrum with only one broad peak at 275 nm is observed. Activation energy of 0.13 eV ± 0.02 eV, which is close to that necessary for migration of H centers, is obtained from the annealing data. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Zn(II) and Ni(II) complexes with poly-histidyl peptides derived from a snake venom
2018
Abstract The snake venoms are complex mixtures containing many bioactive peptides and proteins; some of them are aimed to protect the snake glands, where the venom is stored, until the latter is inoculated in the victim. In the venom of some vipers of the genus Atheris , a set of peptides containing poly-His and poly-Gly segments was recently found. Poly-His peptides are not rare in Nature. Although their exact biological function is most often unknown, one thing is certain: they have good binding properties towards the transition metal ions. As a matter of fact, the imidazole side chain of histidine is one of the groups most frequently involved in metal complexation in the active sites of …