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Before the spread of the Internet, everyone dealt with letters and stamps. One of the pastimes of that time was to separate the stamp from the envelope and keep it. I also had a stamp album when I was a …
This presentation has been prepared to be used as a guide for validating the welding procedure specification (WPS)/procedure qualification record …
In below tables the elements are arranged by atomic number with the year of discovery and the discoverer. The discovery of an element made the discoverer well known and also gave credit to his/her country. Source: Encyclopedia of the Elements, …
It is quite remarkable that only 16, plus a few rare earth elements (REE), of the hundred or so elements …
