Cyclometalated aryl tetra- or trichlorido cyclopentadienyl tantalum complexes [TaXCl(3){C(6)H(4)(2-CH(2)NMe(2))-κ(2)C,N}] (X = Cl 1, η(5)-C(5)H(5)2, η(5)-C(5)H(4)(SiMe(3)) 3, η(5)-C(5)Me(5)4) containing a five-membered TaC(3)N chelate ring were synthesized by reaction of the TaXCl(4) (X = Cl, η(5)-C(5)H(5), η(5)-C(5)H(4)(SiMe(3)), η(5)-C(5)Me(5)) with the appropriate lithium aryl reagent [Li{C(...

OBJECTIVE Functional tissue engineering has emerged as a potential means for treatment of cartilage defect. Development of a stable cartilage composite is considered to be a good option. The aim of the study was to observe whether the incorporation of cultured chondrocytes on porous tantalum utilizing fibrin as a cell carrier would promote cartilage tissue formation. METHODS Rabbit articular ...

At present there is no satisfactory treatment for deep osteochondral defects. Here we report the development of a biologic prosthetic composite containing periosteum from 2-month-old rabbits and a porous tantalum scaffold. When cultured under chondrogenic conditions, the composites form a robust hyaline-like cartilage outgrowth that is attached to the porous scaffold by fibrous tissue ingrowth....

An XRF analyser suitable for measuring up to 15 liters of slurry has been tested in the laboratory. A range of slurries consisting of approximately 40 wt% solids and low concentrations of tantalum were obtained and measured. The accuracy of the analyser has been determined to be ±2 ppm (1 sigma). Improvements are planned that will significantly increase the speed and accuracy of the analyser an...

The molecule (cycloheptatrienyl)(cyclopentadienyl)tantalum, (C(5)H(5))Ta(C(7)H(7)) (1), and its methylcyclopentadienyl and pentamethylcyclopentadienyl analogues (C(5)H(4)Me)Ta(C(7)H(7)) (2), and (C(5)Me(5))Ta(C(7)H(7)) (3) have been synthesized by magnesium reduction of the corresponding (C(5)R(5))TaCl(4) species in the presence of cycloheptatriene. The crystal structures of 2 and 3 show that t...

Nanoparticles of potassium tantalate (KTaO3) and potassium niobate (KNbO3) were synthesized by oxidation of metallic tantalum in molten potassium nitrate with the addition of potassium hydroxide. Magnetization curves obtained on these ferroelectric nanoparticles exhibit a weak ferromagnetism, while these compounds are nonmagnetic in a bulk. The experimental data are used as a start point for th...