One thousand hertz or cycles per second. Symbol kHz.
A simple response to environmental stimuli in which the animal's response is proportional to the intensity of stimulation; it involves a change in speed of movement or rate of turning. Unlike a taxis, the animal
The lightest possible impression on paper so that the type or blocks do not press into the paper, requiring careful make-ready; also required when printing rubber or plastic plates to avoid distortion,
Regular vortex pattern behind an obstacle in a flow where vortices are generated and travel away from the object. The frequency of vortex generation is determined by the Strouhal number,
A paired organ for the excretion of nitrogenous waste products in vertebrates,
A chemical signal produced by one species of animal which influences the behaviour of members of another species, to the benefit of the recipient. Cf allomone.
Protrusion of the innermost layer Des- Cemet's membrane of the cornea through a corneal ulcer,
The topmost joint of a drill string, attached below to the next drill joint and above to the swivel and mudhose connection. It is a heavy tubular part of square or hexagonal cross- section externally which fits into the corresponding hole of the kelly bushing, itself fixed to the rotary table. To add a fresh pipe to the drill string, it has to be raised by the draw works until the kelly and bushing are clear of the rotary table. The string is then locked by wedge- shaped slips to the table and the kelly joint unscrewed and parked in the rat hole. After a new pipe has been attached the kelly is rescrewed and the whole string lowered so that drilling can be restarted. See panel on Drilling rig.
The reaction products of ketones with hydroxylamine, containing the oximino group =NOH attached to the carbon atom,
The process of fitting a key to the key-ways in a shaft and boss.