Self-organization of dislocation structures, slip line and band patterning, and macroscopic plastic instabilities are typical manifestations, at different scales of observation, of nonlinear cooperative phenomena. This general aspect is discussed with emphasis on the relations between the dynamic properties of dislocations, their collective behavior, the local plastic properties of a material a...

Vacuum.-By creating a vacuum the process of decalcification can be characterized as follows: Insoluble calciurn-salts+acid o-soluble calciumsalts+CO2. The carbon dioxide, rapidly extracted, will disturb the balance of the chemical equilibrium, and, according to Le Chatelier, result in an acceleration of the reaction. Waerhaug (1949), however, points out that there will be a more intensive conta...

: The COVID-19 is an infectious disease caused by a newly discovered coronavirus (SARS-CoV-2) and mainly considered respiratory tract illness, even though it may influence other body functions. virus spreads primarily through droplets of saliva or discharge from the nose when infected person coughs sneezes. number people deaths associated with increasing on daily basis current third wave pandem...