Graphite furnace techniques are characterized by excellent analytical sensitivity. They are methods of choice for the determination of trace elements in various environmental, biological, and clinical samples. However, they can be plagued by chemical and background interferences which complicate methods development and sample analysis. Using the graphite platform technique, these interferences ...

Numerical simulations of combustion in aircraft engines is quite complex, as it requires an adequate description of liquid fuel injection, liquid fuel atomization, drop breakup, drop dynamics, and evaporation, large-scale turbulent fuel air mixing, small scale molecular fuel air mixing, chemical reactions, and turbulence/chemistry interactions. In the present paper, we have identified three of ...

The unique meta-GGA (generalized gradient approximation) exchange functional of Becke and Roussel (BR89) and the correlation functional of Becke related to it (B94) are represented for the first time in an analytical form. All functional derivatives are then obtained analytically, which allows an efficient self-consistent implementation. A brief assessment of this "BR89B94" meta-GGA scheme is m...

Shifted contour auxiliary field Monte Carlo is implemented for molecular electronic structure using a plane-waves basis and norm conserving pseudopotentials. The merits of the method are studied by computing atomization energies of H2, BeH2, and Be2. By comparing with high correlation methods, DFT-based norm conserving pseudopotentials are evaluated for performance in fully correlated molecular...

A method of video flame detection based on multi-feature fusion is presented in this paper. Physical characteristics of flame, including color clues, flame movement and flame flicker are incorporated into the scheme to detect fires in color video frames. Firstly, mean filtering was used to smooth the video frames and a flame color filtering algorithm was adopted to extract flame candidate regio...

Sound wave propagation arising from the highfrequency acoustic irradiation of a fluid can generate considerable stresses at the free surface of the fluid leading toward its destabilization and subsequent breakup. If the fluid comprises a polymer solution, the evaporation of the solvent from the aerosols that are generated as a consequence of the atomization process leaves behind a solidified po...

We present a study of the flame-embedding concept, introduced in [1] as an efficient approach for large-eddy simulation of turbulent combustion at high Reynolds and Damköhler numbers. In flame embedding, the combustion zone is modeled as an unsteady flame modified by the local tangential strain rate, with the latter extracted every time step from the flow field simulations. The flame structure ...

 Flash Boiling atomization is one of the most effective means of generating a fine and narrow-dispersed spray. Unless its complexity its potential has not been fully realized. In This Paper, a three dimensional chamber has been modeled with a straight fuel injector. Effect of Flash Boiling has been investigated by computational fluid dynamics (CFD) techniques. A finite volume approach with the ...

We explore the detailed structure of heat release and the energy budget for a freely-propagating lean, premixed hydrogen flame. At lean conditions, the flame is thermodiffusively unstable and spontaneously develops the cellular burning structures, characteristic of this type of flame. The instabilities in the system saturate quickly, resulting in robust, slowly evolving cellular burning feature...