Transient Response of Shells of Revolution by Direct Integration and Modal Superposition Methods

The results of an analytical effort to obtain and evaluate transient response data for a cylindrical and a conical shell by use of two different approaches: direct integration and modal superposition are described. The inclusion of nonlinear terms is more important than the inclusion of secondary linear effects (transverse shear deformation and rotary inertia) although there are thin-shell structures where these secondary effects are important. The advantages of the direct integration approach are that geometric nonlinear and secondary effects are easy to include and high-frequency response may be calculated. In comparison to the modal superposition technique the computer storage requirements are smaller. The advantages of the modal superposition approach are that the solution is independent of the previous time history and that once the modal data are obtained, the response for repeated cases may be efficiently computed. Also, any admissible set of initial conditions can be applied

Investigating correlation of faecal indicator bacteria and potential pathogenic fungi on Dublin beaches in the interest of public health

Sandy beaches are usually the preferred location for leisure activities but may pose a risk to public health in particular to children, the elderly and immuno compromised individuals Beach sand and marine water may be a reservoir of opportunistic and pathogenic microbes, as well as faecal indicator bacteria (that influence the bathing water quality status. The growth and the proliferation of microbes in beach sand and water are not restricted to bacteria but include also different groups of fungi such as potentially pathogenic and allergenic moulds, yeasts and dermatophytes Currently, no clear guidance about pathogenic fungi levels in relation to public health is available for these environments.info:eu-repo/semantics/publishedVersio

Regenerative fuel cell combines high efficiency with low cost

Hydrogen/oxygen regenerative fuel cell stores electrical energy efficiently and inexpensively. The fuel cell has a high energy-to-weight ratio, and is adapted for a large number of cycles with deep discharge

Vibrational state dependence of ionic rotational branching ratios in resonance enhanced multiphoton ionization of CH

We show that rapid evolution of a Rydberg orbital with internuclear distance in a resonance enhanced multiphoton ionization (REMPI) process can have a profound influence on the production of molecular ions in alternative rotational states. This is illustrated by calculations of ionic rotational branching ratios for (2+1′) REMPI via the O11 (20.5) branch of the E′ ^2Σ^+(3pσ) Rydberg state of CH. The rotational propensity rule for ionization changes from ΔN=odd (ΔN=N_+−N_i) at lower vibrational excitation, as expected from the ΔN+l=odd selection rule, to ΔN=even at higher vibrational levels. This effect is expected to be quite general and should be most readily observable in diatomic hydrides