The mechanical properties and good biocompatibility of zirconium and some of its alloys make these materials good candidates for biomedical applications. The attractive in vivo performance of zirconium is mainly due to the presence of a protective oxide layer. In this preliminary study, the surface of pure zirconium modified by anodisation in acidic media at low potentials to enhance its barrie...

A 51 yr old, nonsmoking female suffered from relapsing progressive pneumonia for several years. The patient had worked for 16 yrs in the nuclear industry and was exposed to grinding particles and welding fumes working with zirkaloy, an alloy containing tin, iron, chromium and zirconium. During an exacerbation of the pneumonia radiography of the lung showed interstitial infiltrations of both low...

Modification of different zirconium propoxide precursors with H(2)dea was investigated by characterization of the isolated modified species. Upon modification of zirconium n-propoxide and [Zr(O(n)Pr)(O(i)Pr)(3)((i)PrOH)](2) with (1/2) a mol equivalent of H(2)dea the complexes [Zr(2)(O(n)Pr)(6)(OCH(2)CH(2))(2)NH](2) (1) and [Zr(2)(O(n)Pr)(2)(O(i)Pr)(4)(OCH(2)CH(2))(2)NH](2) (2) were obtained. Ho...

Films of highly oriented alpha-zirconium phosphate and polyaniline-intercalated zirconium phosphate with controllable thickness in the micrometer range were grown anodically on Pt electrodes. To optimize the electrodeposition conditions, the exfoliation of alpha-zirconium phosphate by tetrabutylammonium (TBA) salts was investigated in several nonaqueous solvents. Acetonitrile was found to be th...

Ultra-High Temperature Ceramic Matrix Composites (UHTCMCs) are the next generation composites developed for application in harsh environment of aerospace. Qualification these materials requires manufacturing demonstrators testing relevant environments, which turn, to scale them up. This paper illustrates systematic approach adopted scale-up UHTCMCs based on carbon fibre reinforced zirconium dib...

Two new intercalates of tris[4-(pyridin-4-yl)phenyl]amine (TPPA) with zirconium hydrogen phosphate and zirconium 4-sulfophenylphosphonate having formulae Zr(HPO4)2·0.21(C33H24N4)·2.5H2O and Zr(HO3SC6H4PO3)(1.3)(C6H5PO3)(0.7)·0.35(C33H24N4)·2.5H2O were prepared and characterized by thermogravimetry, IR spectroscopy, and powder X-ray diffraction. The TPPA molecule has been selected as a model tri...

Ternary hybrid film composed of -zirconium phosphate nanosheet, 1,2-bis(dimethylchlorosilyl)ethane and polypyrrole was prepared by anodic electrodeposition. In the hybrid film, ordered -zirconium nanosheets with grafts by silylation lay down parallel to the substrate and the polypyrrole molecules were intercalated between the nanosheets. The electrochemical measurements confirmed that the hyb...

Investigations of voltammetry zirconium deposition from DMSO solution on different substrates were taken. It was found that this is multi-electron process proceeding in a few stages. Moreover, zirconium layers were obtained on titanium, copper stainless steel and nickel. Obtained deposit was in form of white powder, which immediately was oxidized to ZrO2 in the presence of air.

PURPOSE The aim of this work is to evaluate different types of materials used for making implant abutments, by means of an in vitro study and a review of the literature, in order to identify the indications for a better choice of an implant-supported restoration in the anterior section. MATERIALS AND METHODS 5 implant abutments were tested in a random order in the superior anterior maxilla of...

OBJECTIVES Providing reliable attachment between bracket base and zirconia surface is a prerequisite for exertion of orthodontic force. The purpose of the present study was to evaluate the effect of four zirconium surface treatment methods on shear bond strength (SBS) of orthodontic brackets. MATERIALS AND METHODS One block of zirconium was trimmed into four zirconium surfaces, which served a...