Variances involved in estimating the abundance of the nitrogen-fixing marine cyanobacterium, Trichodesmium Ehrenberg, were evaluated by repeated sampling using bottle casts and plankton net tows at two stations in the southern East China Sea. The variance among individual samples and the variance arising from subsampling processes were separated by the method of analysis of variance, and the co...

Fibrous tows used in continuous fibre-reinforced polymers (CFRPs) deform geometrically during the production of composite products. The cross-sectional geometry of the tow is influenced by the load-induced deformation mechanisms. A study of the effect of two commonly assumed geometrical tow shapes on an equivalent pressure distribution in a tow-on-a-pin spreading arrangement was performed. The ...

Ion engines accelerate electrically charged plasma through two optic grids and emit the ions as exhaust. The process facilitates propulsion without use of chemical propellants. Braided carbon fiber reinforced composite (C(f)/C) optics are presently being considered for use as the accelerator and screen grids in ion propulsion engines. In this study the mechanical behavior of four candidate tow ...

Elasmobranchs can detect minute electromagnetic fields, <1 nV cm(-1), using their ampullae of Lorenzini. Behavioural responses to electric fields have been investigated in various species, sometimes with the aim to develop shark deterrents to improve human safety. The present study tested the effects of the Shark Shield Freedom7™ electric deterrent on (1) the behaviour of 18 white sharks (Carch...

The Department of Energy Freedom Car Program has shown that domestic vehicle fuel consumption can be dramatically decreased by reducing the overall weight of production vehicles. Carbon fiber composites provide an attractive route to this goal. Significant automotive use of carbon fiber technology will require substantial increases in fiber production coupled with decreases in fiber price to ~$...

In the past several years, capabilities of optical tools and in situ imaging devices have greatly expanded are now revolutionizing field plankton research. These facilitated discovery new enhanced understanding populations fragile gelatinous zooplankton. Imaging becoming more accessible regularly deployed on oceanographic studies monitoring efforts. However, despite increasing use these tools, ...

In an on-going effort to increase the safety and efficiency of turbine engines, the National Aeronautics and Space Administration is exploring lightweight alternatives to the metal containment structures that currently encase commercial jet engines. Epoxy reinforced with braided carbon fibers is a candidate structural material which may be suitable for an engine case. This paper reports flat-co...

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