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1.
Acta Orthop Belg ; 88(2): 303-309, 2022 Jun.
Article in English | MEDLINE | ID: mdl-36001836

ABSTRACT

Contemporary uncemented femoral revision hip systems have become commonly used over the past decade and have enabled the reconstruction of leg length, offset and anteversion as independent variables through the use of modular junctions. Modular junction failures between the proximal body and distal stem have been described with revision systems, although this is rare. We sought to identify the survivorship of one revision system in a salvage arthroplasty scenario where no host bone support of the modular junction was present. From a series of 136 patients, 15 patients (16 hips) were identified without host bone support of the modular junction with a mean radiological follow up of over 6 years (76 months +/- 35 months). There have been no cases of prosthetic fracture over the follow-up duration, with two revisions performed for reasons of aseptic loosening and infection. The mean BMI of the study group was 30.2 with 78% of the cohort classified as overweight or obese. It is well recognised that, host bone support of the modular junction is preferable, however the satisfactory outcomes over the midterm in these complex patients suggests that modular revision systems remain an option.


Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Arthroplasty, Replacement, Hip/adverse effects , Femur/surgery , Hip Prosthesis/adverse effects , Humans , Prosthesis Design , Prosthesis Failure , Reoperation , Retrospective Studies , Survivorship , Treatment Outcome
2.
Chem Sci ; 7(8): 4832-4841, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-30155131

ABSTRACT

We report the synthesis and photoelectrochemical assessment of phase pure tetragonal matlockite structured BiOX (where X = Cl, Br, I) films. The materials were deposited using aerosol-assisted chemical vapour deposition. The measured optical bandgaps of the oxyhalides, supported by density functional theory calculations, showed a red shift with the increasing size of halide following the binding energy of the anion p-orbitals that form the valence band. Stability and photoelectrochemical studies carried out without a sacrificial electron donor showed the n-type BiOBr film to have the highest photocurrent reported for BiOBr in the literature to date (0.3 mA cm-2 at 1.23 V vs. RHE), indicating it is an excellent candidate for solar fuel production with a very low onset potential of 0.2 V vs. RHE. The high performance was attributed to the preferred growth of the film in the [011] direction, as shown by X-ray diffraction, leading to internal electric fields that minimize charge carrier recombination.

3.
Sci Rep ; 5: 10952, 2015 Jun 04.
Article in English | MEDLINE | ID: mdl-26042724

ABSTRACT

Tungsten doped titanium dioxide films with both transparent conducting oxide (TCO) and photocatalytic properties were produced via aerosol-assisted chemical vapor deposition of titanium ethoxide and dopant concentrations of tungsten ethoxide at 500 °C from a toluene solution. The films were anatase TiO2, with good n-type electrical conductivities as determined via Hall effect measurements. The film doped with 2.25 at.% W showed the lowest resistivity at 0.034 Ω.cm and respectable charge carrier mobility (14.9 cm(3)/V.s) and concentration (×10(19) cm(-3)). XPS indicated the presence of both W(6+) and W(4+) in the TiO2 matrix, with the substitutional doping of W(4+) inducing an expansion of the anatase unit cell as determined by XRD. The films also showed good photocatalytic activity under UV-light illumination, with degradation of resazurin redox dye at a higher rate than with undoped TiO2.

4.
Sci Technol Adv Mater ; 15(6): 065003, 2014 Dec.
Article in English | MEDLINE | ID: mdl-27877733

ABSTRACT

Silica microfiber wool was systematically functionalized in order to provide an extremely water repellent and oleophilic material. This was carried out using a two-step functionalization that was shown to be a highly effective method for generating an intense water repulsion and attraction for oil. A demonstration of the silica wools application is shown through the highly efficient separation of oils and hydrophobic solvents from water. Water is confined to the extremities of the material, while oil is absorbed into the voids within the wool. The effect of surface functionalization is monitored though observing the interaction of the material with both oils and water, in addition to scanning electron microscope images, x-ray photoelectron spectroscopy and energy dispersive x-ray analysis. The material can be readily utilized in many applications, including the cleaning of oil spills and filtering during industrial processes, as well as further water purification tasks-while not suffering the losses of efficiency observed in current leading polymeric materials.

5.
Langmuir ; 30(2): 624-30, 2014 Jan 21.
Article in English | MEDLINE | ID: mdl-24354409

ABSTRACT

PbO clusters were deposited onto polycrystalline titanium dioxide (anatase) films on glass substrates by aerosol-assisted chemical vapor deposition (AACVD). The as-deposited PbO/TiO2 films were then tested for visible light photocatalysis. This was monitored by the photodegradation of stearic acid under visible light conditions. PbO/TiO2 composite films were able to degrade stearic acid at a rate of 2.28 × 10(15) molecules cm(-2) h(-1), which is 2 orders of magnitude greater than what has previously been reported. The PbO/TiO2 composite film demonstrated UVA degradation of resazurin redox dye, with the formal quantum yield (FQY) and formal quantum efficiency (FQE) exceeding that of a TiO2 film grown under the same conditions and Pilkington Activ, a commercially available self-cleaning glass. This work correlates with computational studies that predicted PbO nanoclusters on TiO2 form active visible light photocatalysts through new electronic states through PbO/TiO2 interfacial bonds resulting in new electronic states above the valence band maximum in TiO2, shifting the valence band upward as well as more efficient electron/hole separation with hole localization on PbO particles and electron on the TiO2 surface.


Subject(s)
Lead/chemistry , Light , Oxides/chemistry , Titanium/chemistry , Catalysis , Particle Size , Photochemical Processes , Surface Properties
6.
Phys Chem Chem Phys ; 15(39): 16788-94, 2013 Oct 21.
Article in English | MEDLINE | ID: mdl-23999866

ABSTRACT

Boron-doped titanium dioxide (B-TiO2) films were deposited by atmospheric pressure chemical vapour deposition of titanium(iv) chloride, ethyl acetate and tri-isopropyl borate on steel and fluorine-doped-tin oxide substrates at 500, 550 and 600 °C, respectively. The films were characterised using powder X-ray diffraction (PXRD), which showed anatase phase TiO2 at lower deposition temperatures (500 and 550 °C) and rutile at higher deposition temperatures (600 °C). X-ray photoelectron spectroscopy (XPS) showed a dopant level of 0.9 at% B in an O-substitutional position. The ability of the films to reduce water was tested in a sacrificial system using 365 nm UV light with an irradiance of 2 mW cm(-2). Hydrogen production rates of B-TiO2 at 24 µL cm(-2) h(-1) far exceeded undoped TiO2 at 2.6 µL cm(-2) h(-1). The B-TiO2 samples were also shown to be active for water oxidation in a sacrificial solution. Photocurrent density tests also revealed that B-doped samples performed better, with an earlier onset of photocurrent.

7.
Chemistry ; 17(41): 11613-21, 2011 Oct 04.
Article in English | MEDLINE | ID: mdl-21882265

ABSTRACT

The use of an aerosol delivery system enabled fluorine-doped tin dioxide films to be formed from monobutyltin trichloride methanolic solutions at 350-550 °C with enhanced functional properties compared with commercial standards. It was noted that small aerosol droplets (0.3 µm) gave films with better figures of merit than larger aerosol droplets (45 µm) or use of a similar precursor set using atmospheric pressure chemical vapour deposition (CVD) conditions. Control over the surface texturing and physical properties of the thin films were investigated by variation in the deposition temperature and dopant concentration. Optimum deposition conditions for low-emissivity coatings were found to be at a substrate temperature of about 450 °C with a dopant concentration of 1.6 atm% (30 mol% F:Sn in solution), which resulted in films with a low visible light haze value (1.74%), a high charge-carrier mobility (25 cm(2) V s(-1)) and a high charge-carrier density (5.7×10(20) cm(-3)) resulting in a high transmittance across the visible (≈80%), a high reflectance in the IR (80% at 2500 nm) and plasma-edge onset at 1400 nm. Optimum deposition conditions for coatings with applications as top electrodes in thin film photovoltaics were found to be a substrate temperature of about 500 °C with a dopant concentration of 2.2 atm% (30 mol% F:Sn in solution), which resulted in films with a low sheet resistance (3 Ω sq(-1)), high charge-carrier density (6.4×10(20) cm(-3)), a plasma edge onset of 1440 nm and the films also showed pyramidal surface texturing on the micrometer scale which corresponded to a high visible light haze value (8%) for light scattering and trapping within thin film photovoltaic devices.

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