New volatile polyazolylborates of copper(I) for MOCVD

The volatility of new bis- and tetrakis-(pyrazo1yl)borates of copper(1) with monodentate tertiary phosphines recently prepared has been prepared by the reaction between CuCI, phosphine and KBH2pz2 or KBpz, in CH3CN (Hpz is a pyrazole-type ligand) has been studied. The IR data in gas in a vast temperature region confirm the stability of precursors in vapour, suggesting the molecular structure in vapour being similar to that determined previously by X-ray difiaction. The dependence of the volatility on the number of the pyrazolyl-moieties and nature of phosphine is discussed. Film growth rates obtained &om MOCVD experiments, as well as XRD and SEM data for copper films deposited by using [CU&B(~~)~(PM~P~~)~] as precursor are reported

Structure and volatility of copper complexes containing pyrazolyl-based ligands

Volatility studies, electrospray mass spectra and IR in vapour phase were carried out for a series of Cu(I) and Cu(II) complexes containing anionic pyrazole-based ligands such as 4-acyl-5-pyrazolonates and poly(pyrazolyl)borates. The volatility has been related to structural features and molecular parameters of the copper complexes. The crystal structures of [Cu(Q′)2(bipy)]·(acetone)1.5 (Q′=1-phenyl-3-methyl-4-benzoyl-pyrazolon-5-ato, bipy=2,2′-bipyridyl) and [Cu(QF)2(phen)]·EtOH (QF=1-phenyl-3-methyl-4-trifluoroacetyl-pyrazolon-5-ato, phen=1,10-phenanthroline), have been also determined. In these complexes the copper atom is in a tetragonally distorted octahedral arrangement of the four O-atoms of pyrazolones with N2-donor ligand in equatorial position. Two sets of CuO distances, the longer being in axial positions, have been found. XRD data of films obtained from metal organic chemical vapour deposition MOCVD experiments on [Cu(poly(pyrazolyl)borate)(PR3)] complexes have also been reported

Histomorphometric, ultrastructural and microhardness evaluation of the osseointegration of a nanostructured titanium oxide coating by metal-organic chemical vapour deposition: an in vivo study

Over the past decade the increase of elderly population has determined a rise in the incidence of bone fractures, and the improvement of the implant\u2013bone interface remains an open problem. Metal-organic chemical vapour deposition (MOCVD) has recently been proposed as a technique to coat orthopaedic and dental prostheses with metal nanostructured oxide \ufb01lms either through the decomposition of oxygenated compounds (single-source precursors) or the reaction of oxygen-free metal compounds with oxygenating agents. The present study was performed to assess the in vivo biocompatibility of commercially pure Ti (control material: TI/MA) implants (+ 2 mm5 mm length) coated with nanostructured TiO2 \ufb01lms by MOCVD (Ti/MOCVD) and then inserted into rabbit femoral cortical (middhiaphysis) and cancellous (distal epiphysis) bone. Histomorphometric, ultrastructural and microhardness investigations were carried out. Four and 12 weeks after surgery, signi\ufb01cant (po0:0005) increases in AI of Ti/ MOCVD implants were observed as compared to Ti/MA implants (distal femoral epiphysis: 4 weeks=8.2%, ns; 12 weeks=52.3%, po0:005; femoral diaphysis: 4 weeks=20.2%, po0:0005; 12 weeks=10.7%, po0:005). Bone microhardness results showed signi\ufb01cant increases for the Ti/MOCVD versus Ti/MA implants at 200mm in the femoral diaphysis (4 weeks=14.2, po0:005) and distal femoral epiphysis (12 weeks=14.5, po0:01) at 4 and 12 weeks, respectively. In conclusion, the current \ufb01ndings demonstrate that the nanostructured TiO2 coatingpositively affects the osseointegration rate of commercially pure Ti implants and the bone mineralization at the bone\u2013biomaterial interface in both cortical and cancellous bon

Estimating the biological half-life for radionuclides in homoeothermic vertebrates: a simplified allometric approach

The application of allometric, or mass-dependent, relationships within radioecology has increased with the evolution of models to predict the exposure of organisms other than man. Allometry presents a method of addressing the lack of empirical data on radionuclide transfer and metabolism for the many radionuclide–species combinations which may need to be considered. However, sufficient data across a range of species with different masses are required to establish allometric relationships and this is not always available. Here, an alternative allometric approach to predict the biological half-life of radionuclides in homoeothermic vertebrates which does not require such data is derived. Biological half-life values are predicted for four radionuclides and compared to available data for a range of species. All predictions were within a factor of five of the observed values when the model was parameterised appropriate to the feeding strategy of each species. This is an encouraging level of agreement given that the allometric models are intended to provide broad approximations rather than exact values. However, reasons why some radionuclides deviate from what would be anticipated from Kleiber’s law need to be determined to allow a more complete exploitation of the potential of allometric extrapolation within radioecological models