helicopter-borne electromagnetic (hem) is a fast and high resolution airborne electromagnetic (aem) method that is frequently used for imaging of the subsurface resistivity structures. this is a versatile and cost effective method, frequently has used in mineral and groundwater exploration and various environmental problems. modern frequency-domain hem systems utilize small electromagnetic, mag...

The objective of this study was to develop a methodology by which the risk from major accident hazards to the environment can be assessed or quantified. An index method, the Environmental Risk Index (ERI), has been developed based on an existing method, the Environmental Hazard Index (EHI), and the Department of the Environment (DoE) definitions of events that would constitute a major accident ...

Using the Ziman-formulation a model is derived which describes the pressure dependence of the electrical resistivity of d-electron amorphous alloys. It is shown how the volume dependence of the scattering-potential, electron-gas-properties and the Grüneisenparameter determine the P-dependence of a constant and a temperature dependent term in the resistivity. The absolute value of the resistivit...

This numerical study examines the importance of self-consistently accounting for transport and electrostatics in the calculaiton of semiconductor/metal Schottky contact resistivity. It is shown that ignoring such self-consistency results in significant under-estimation of the contact resistivity. An explicit numerical method has also been proposed to efficiently improve contact resistivity calc...

Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engine...

During vessel evolution in angiosperms, scalariform perforation plates with many slit-like openings transformed into simple plates with a single circular opening. The transition is hypothesized to have resulted from selection for decreased hydraulic resistance. Previously, additional resistivity of scalariform plates was estimated to be small – generally 10% or less above lumen resistivity – ba...

Six methods have given squid axoplasm resistivities of from 1.0 to 6.9 times seawater (X SW), so another was tried. A 100-mum platinized electrode was to be inserted from each end of an axion in iso-osmotic sucrose and impedance between them measured vs. separation. But observations that the resistance of axons in sucrose increased steadily ruled this out. Axoplasm from two or three axons was t...

The effect of surface phonon scattering on the electrical resistivity has been observed in Co/Ni superlattices, with reproducible film microstructure, independent of the film thickness. The temperaturedependent part of the resistivity increases rapidly with decreasing film thickness for films thinner than the electronic mean free path. The resistivity shows a universal behavior well characteriz...