Tin, lead and their alloys, due to their low melting temperatures and wide availability, are the most commonly used solder materials. In fact, lead has been used as a soldering metal for water pipes (also made of lead) even in Roman times, hence the scientific name for lead, Plumbum. Mechanical Properties.
hearing impairment - impairment of the sense of hearing. hearing disorder. disability, disablement, handicap, impairment - the condition of being unable to perform as a consequence of physical or mental unfitness; reading disability; hearing impairment. deafness, hearing loss - partial or complete loss of hearing.
The primary auditory cortex is the part of the temporal lobe that processes auditory information in humans and other vertebrates.he auditory cortex was previously subdivided into primary (A1) and seco (A2) projection areas and further association areas. The modern divisions of the auditory cortex are the core (which includes A1), the belt, and the parabelt.