A slurry sample introduction technique for the analysis of TiO 2 powders by axial viewing ICP-OES is reported. Relationships between stable slurries and the conditions, such as particle size, pH, dispersant and its amount, were experimentally investigated. Slurries were prepared by mixing the TiO 2 powder with the dispersant poly(acrylate amine) (NH 4 PAA) and agitation in an ultrasonic bath to ensure good dispersion. The pH of the medium and amount of dispersant has been optimized. Impurities in TiO 2 were determined by an axial viewing ICP-OES spectrometer. As representatives, a Standard Reference Material 154 b of mm particle size TiO 2 and a nm particle size TiO 2 were selected and determined for micro and trace impurities. Analytical results obtained via slurry sample introduction were compared with those via nebulization of aqueous solutions prepared by acid digestion and fusion digestion. The determined results by slurry introduction were in good accordance with the stated values, which verified that the calibration curves could be established by aqueous standards.

Assessment of the energy release rate (ERR) of layered material structures with account for dynamic and vibration effects is important for understanding and predicting fracture behavior in various engineering applications. In this work, the pure-mode-I interfacial fracture behavior of a symmetric double cantilever beam (DCB) under constant-rate opening displacement is studied using a dynamics and vibration analysis of Euler-Bernoulli beams, and the ERR is derived. Furthermore, a 'dynamic factor' that quantifies the dynamic effect in relation to the static component of ERR is defined. The resulting expressions are relatively short, mathematically elegant and convenient-to-use by engineers and researchers, which increases their usefulness. It is found that the dynamic factor is a function of the characteristic time only, and that this is an intrinsic property of DCB structures. An approximate method is also proposed to predict the crack extension. Predictions of ERR and crack extension are in good agreement with results from numerical results with finite-element method (FEM) simulations. Using only the first vibration mode is sufficient to capture the amplitude and frequency of ERR variation predicted by the FEM. Using higher-order vibration modes causes divergence in the amplitude of ERR oscillation; this is due to the limitation of Euler-Bernoulli beams in vibration analysis.

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Analytical theory for the dynamic delamination behavior of a double cantilever beam (DCB) under high loading rate is developed. Structural vibration and wave dispersion are considered in the context of Euler-Bernoulli beam theory. The theory is developed for both initiation and propagation of delamination in mode I. Two solutions for the energy release rate (ERR) are given for a stationary delamination: an accurate one and a simplified one. The former is based on global energy balance, structural vibration and wave dispersion; the latter is 'local' since it is based on the crack-tip bending moment. For the simplified solution to be accurate, sufficient time is needed to allow the establishment of all the standing waves. For a propagating delamination, a solution for the ERR is derived using the same simplification with the cracktip bending moment. The obtained ERR solutions are verified against experimental data and results from finite-element simulations, showing excellent agreement. One valuable application of the developed theory is to determine a material's dynamic loading-ratedependent delamination toughness by providing the analytical theory to post-process test results of dynamic DCB delamination.