Interference in solar oscillations

We have analyzed magnetograph observations of the 5-min oscillations. We find that most of the oscillatory power is concentrated in space and frequency. Interference effects where these concentrations overlap can explain some of the variations in amplitude of the oscillation.Of the National Bureau of Standards and University of Colorado.     

On the Use of Computational Fluid Dynamics to Investigate Aerosol Dispersion in an Industrial Environment: A Case Study

Aerosol dispersion in the area surrounding an existing biological treatment facility is investigated using large-eddy simulation, with the objective to investigate the applicability of computational fluid dynamics to complex real-life problems. The aerosol sources consist of two large aeration ponds that slowly diffuse aerosols into the atmosphere. These sources are modelled as dilute concentrations of a non-buoyant non-reacting pollutant diffusing from two horizontal surfaces. The time frame of the aerosol release is restricted to the order of minutes, justifying a statistically steady inlet boundary condition. The numerical results are compared to wind-tunnel experiments for validation. The wind-tunnel flow characteristics resemble neutral atmospheric conditions with a Reynolds number, based on the boundary-layer thickness, of Re _δ ≈ 2 × 10⁵. The numerical inflow conditions are based upon the wind-tunnel flow field. The predicted decay of both the mean and root-mean-square concentrations are in good agreement with experimental data; at 3 m from the ground, the plume mean concentration 200 m downwind of the source is approximately 2% of the source strength. The numerical data in the near-surface layer (0–50 m from the ground) correspond particularly well with the wind-tunnel data. Tentative deposition simulations suggest that there seems to be little difference in the deposition rates of large (1.8 × 10⁻⁵ m) and small (3 × 10⁻⁶ m) particles in the near-field under the flow conditions considered.     

Laxmi Ridge – A continental sliver in the Arabian Sea

Identification by Bhattacharya et al. (1994) of seafloor spreading type magnetic anomalies in the basin lying between Laxmi Ridge in the Arabian Sea and the Indian continent necessitates a change in plate tectonic reconstruction. Naini and Talwani (1982) named this basin the Eastern Basin and we will continue to use this term in this paper. Others, in the literature, have called this the Laxmi Basin. Previous reconstructions had assumed that the Eastern Basin is underlain by continental crust. The new reconstruction moves Seychelles' original location closer to India and ameliorates a space problem in the Mascarene Basin. A new rotation pole between anomaly 28 and 34 times avoids skipping of fracture zones resulting from rotation poles described earlier. The negative gravity anomaly over the Eastern Basin is a necessary consequence of a continental sliver lying between oceanic crust on either side. Seismic velocities that are slightly greater than 7 km s^–1 under the Eastern need not be necessarily interpreted as material that underplates continental crust.