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Byline: K. Madhusudan Reddy, Smita. Vimala, G. Umamaheswara Rao Sir, Vascular injury during lumbar disc surgery is rare but can be catastrophic. We report the occurrence of iliac artery injury [...]

1-g model experiments were carried out in the laboratory to investigate the behavior of a single pile in sand under combined uplift and lateral load. Dimensions of the model pile were ascertained using physical scaling laws, based on adopted material properties of model and prototype pile foundations. The model pile is made up of aluminum and has outer and inner diameters of 25.4 and 19.0 mm, respectively. Different length-to-diameter ratios of 18, 28, and 38 are considered by varying the pile length to simulate behavior of both stiff and flexible piles. The test tank dimensions were chosen such that boundary effects are minimized. The size of the model steel tank is 1.0 x 1.0 x 1.2 m (depth). Experiments were performed on single piles embedded in sandy soil under independent uplift and lateral loading, and combined lateral and uplift loading. Results indicate that the load-deflection behavior is nonlinear for independent uplift and lateral load tests, as well as in the case of combined loading. It is also observed that the behavior of piles under independent loading is substantially different when compared to combined loading. It is found that the ultimate lateral/uplift load capacity under combined loading increased considerably; however, the pile head deflection/displacement at safe lateral/uplift load is found to increase under combined loading. This indicates that although the capacity is increasing under combined load, considering this increased pile capacity may not be possible in a practical design. Rather the safe lateral/uplift loads that are being used in the current design may need to be verified for satisfying the limiting deflection/displacement criteria of the piles considering the effect of combined loading. [ABSTRACT FROM AUTHOR]

By variation of reaction temperature and time during the hydrothermal synthesis process, TiO2 nanoparticles in anatase, rutile, and mixture of rutile-anatase phases are formed without adding any mineralizer. Differential thermal analysis studies indicate the rutile phase crystallization at a comparatively lower temperature and a low weight loss. The material synthesized by hydrothermal reaction required no post-calcination for the crystallization. Transmission electron microscopy, selected-area diffraction, Brunauer-Emmett-Teller, and x-ray diffreaction studies confirmed the compositions to be anatase and rutile with the particle size ranging from 5 to 25 nm with surface area as high as 260 m²/g for the anatase and 65 m⊃2/g for ruffle. The prepared nanoparticles exhibited a blue shift of the absorption edge in the ultraviolet-visible spectrum greater than 10 nm. The particles with average size around 5 nm showed two band edges in the absorption spectra attributed to two different particle sizes. Simple photocatalytic reactions were tried to demonstrate the photochemical activity of the synthesized material. The synthesized nanoparticles exhibited an ultraviolet radiation simultaneous photoreduction of Cr(VI) to Cr(III) and oxidation of formic acid into carbon dioxide and water. [ABSTRACT FROM AUTHOR]

Nickel ferrite, an n-type semiconducting oxide material with cubic spinel (AB2O4) structure, has been synthesized by the hydrothermal process with an average crystallite size of ∼11 nm and surface area of 94 m2 g−1 and characterized by X-ray diffraction (XRD), thermogravimetric analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and Brunner–Emmett–Teller surface analyzer. The pH, temperature, pressure and time of reaction during hydrothermal synthesis has been shown to play a deterministic role in obtaining the semiconducting oxide in the required size regime with improved gas sensing behavior. Incorporation of palladium further improved the sensitivity, response time and selectivity to liquefied petroleum gas (LPG). Palladium incorporated NiFe2O4 (Pd: 1 wt.%) was able to detect up to 25 ppm LPG in air at an operating temperature of 200 °C. The improved gas sensing properties can mainly be attributed to the uniform nanocrystalline particles of the semiconducting oxide obtained by the hydrothermal crystallization, combined with the noble metal additive sensitization. [Copyright &y& Elsevier]