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A cold cathode X-ray tube was fabricated using a carbon nanotube (CNT) field electron emitter made by a free-standing CNT film which is composed of a highly packed CNT network. A lot of CNT bundles with a sharp tip are vertically aligned at the edge of the thin CNT film with a length of 10 mm and a thickness of 7 μm. The cold cathode X-ray tube using the CNT field emitter presents an extremely high tube current density of 152 A/cm

Two experiments investigated what eye movements can reveal about how we process surprising information and how we update mental models in dynamic and unstructured environments. Participants made saccades to visual targets presented one at a time, radially, around an invisible perimeter. Target locations were normally distributed and shifted at an unannounced point during the task. Trials following the shift were considered surprising and unexpected. These unexpected and surprising events prompted the need to update. Slower saccadic latencies were observed for surprising/unexpected events, perhaps indicative of the need to reorient attention to the unexpected target location. Longer dwell times were observed for events that signaled a change in the distribution. These data show that eye movement metrics provide a reliable indicator of mental model updating when contingencies change even in the absence of explicit change signals.

Graphite nanoplatelet (GNP) paste field emitters fabricated using all-carbon-based materials, such as GNPs, graphite nanoparticles, graphite binders, and a graphite rod substrate have been demonstrated. The GNP field emitters on the graphite rod substrate showed an emission current density of 84.3 mA/cm2 and good emission stability with a degradation rate of less than 10%, indicating higher emission performance than other GNP field emitters. The enhanced field emission performance of the GNP field emitter is attributed to a low work function barrier between carbon materials, low contact resistance between GNPs and the graphite rod substrate, and good GNP paste bulk electrical conductivity. The new approach to fabricate GNP field emitters using all-carbon-based materials can be useful for various field emission devices.