Treatment of tetrakis(diethylamido)zirconium(IV); [Zr(NEt2)4] with a series of β-ketoimines ({[RHN]C(CH3)=C(H)C(CH3)=O} where R is a functionalized side-chain; 4-(2-methoxyethylamino)pent-3-en-2-one, Hmeap; 4-(3-methoxypropylamino)pent-3-en-2-one, Hmpap; 4-(2-(dimethylamino)ethylamino)pent-3-en-2-one, Hdeap; 4-(3-(dimethylamino)propylamino)pent-3-en-2-one, Hdpap) leads to an amine substitution ...

Background: Some Particular areas contain natural radionuclide at levels much higher than those usually present in earth's crust. The radiological impact of the use of zirconium ore in zirconium industry is due to internal exposure of the lung by alpha particles and external exposure of the body by the gamma rays. The result of gamma spectrometry measurement of the concentrations of th...

The quadrupole interaction of Ta probes in isostructural C u 8 H f 3 and C u 8 Z r 3 intermetallic compounds was studied in the temperature range 24 K -1100 K with the time-differential perturbed angular correlation technique. Two nonaxial electric field gradients corresponding to two nonequivalent hafnium or zirconium sites in the investigated structure were found. A linear decrease in the qua...

The Baylis-Hillman reactions of various aryl aldehydes with methyl vinyl ketone at temperatures below -20C using Lewis acids such as titanium (IV) chloride, boron (III) chloride or zirconium (IV) chloride in the presence of a catalytic amount of selected amines used as a Lewis bases afford the chlorinated compounds 1 as the major product in very high yields. Acrylonitrile can also undergo the s...

Methyl benzoate (MB) compounds are prepared by reacting various benzoic acids with methanol using an acidic catalyst. In this study, the solid of zirconium metal solids fixed substances were studied. We determined that catalysts Ti had best activity. The catalytic synthesis a series MB titanium was direct condensation acid and metallic Lewis without other auxiliary Bronsted is reported for firs...

The purpose of this study was to compare the fracture resistance and fracture mode of single implant-zirconium coping combinations using zirconium and titanium abutments and to analyze the stress distribution pattern using three-dimensional finite elements analysis. Twenty implants with titanium and zirconium abutments were randomly divided into two groups (n = 10) and into resin blocks. Zircon...

Aim: The aim of this in vitro study was to evaluate imaging artifacts induced by Titanium, Zirconium, Titanium-Zirconium abutments in CT, MRI and CBCT imaging modalities.Methods: A 4×8mm titanium fixture was inserted in a dry human mandible. Titanium, Zirconium and Titanium–Zirconium abutments measuring 10.5 mm in height are located on the fixture, one by one. Each abutment was scan...

The structure of solid zirconium tetrachloride is known from X-ray studies[l] to consist of extended chains of distorted octahedra with two bridging chlorine atoms between adjacent zirconium atoms. Although the unit cell possesses a center of symmetry, the two pairs of bridging chlorine atoms attached to a given zirconium atom are not trans to each other. The factor group symmetry thus is C2h w...

The sol-gel method produces amorphous or crystalline thin gel films of metallic solid compounds by solidifying a sol formed by hydrolyzing and polymerizing a solution containing metallic compounds. Sol-gel processes are widely employed in the field of chemistry to prepare ceramic powders and thin films of hafnium oxide (HfO2) (Nishide et al., 2000) and zirconium oxide (ZrO2) ( Liu et al., 2002)...

We already reported that an intramolecular benzylation of the imino moiety of bidentate iminopyrrolyl ligands afforded an amido-pyrrolyl complexes 1 and they exhibited better catalytic activity for ethylene polymerization compared to the corresponding bis(iminopyrrolyl) dichloro complexes of zirconium. In this contribution, we prepared amido-pyrrolyl complexes of zirconium (3a-d) and hafnium (4...