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 teenager. Therefore, it is not strange that when I started my career as a welding engineer, I looked for the connection between postage stamps and welding.
The file below is the result of that effort.
PS: Unfortunately, I have not written down the references that I used.
Standards organizations can be classified by their role, position, and the extent of their influence on the local, national, regional, and global standardization arena. By geographic designation, there are international, regional, and national standards bodies. By technology or industry designation, …
– شیوع بیماری حصبه، زندگی و کودکی را به او که هنوز ۶ سال بیشتر نداشت تلخ کرد. اول مادرش و پنج روز بعد پدرش درگذشتند و سرپرستی او را پدربزرگش به عهده گرفت. – پس از دارالفنون به دانشسرای …
Stainless steels owe their widespread use to a combination of unique properties that have advantages over those of other steels and nonferrous metals for many applications. The principal outstanding characteristics are their resistance to corrosion in many environments, their good …
