Historically, to describe numbers, some cultures used bases much larger than our usual base 10, namely, 20, 40, and 60. There are explanations for 60, there is explanation but 40—used in medieval Russia—remains largely a mystery. In this paper, we provide possible all these three bases, an based on the natural need manage large groups of people. We also speculate why different bases.

This paper presents a characterization of PA6 and the blend PA6+EPDM (60/40) by tensile tests in order to evaluate several mechanical properties for impact resistance applications. Results were found be dependend on test rate (10 mm/min, 250 mm/min 1000 mm/mm). SEM investigation point out homogenous structure. The has better value energy at break, higher speed: v=250 this characteristic break 2...

According to J.A.N. Lee in 1996, computer scientists “are reaching the stage of development where each new generation of participants is unaware both of their overall technological ancestry and the history of the development of their speciality, and have no past to build upon” [1, p.54]. A technically and historically accurate account, as attempted here, can help us, computer scientists, grasp ...

A new general reaction for the preparation of isomerically pure hydroxyalkylated C(60) monoadducts, via the free radical photochemical addition of alcohols to [60]fullerene, is described.

The formation of polyelectrolyte multilayers (PEMs) for the first time, two decades ago, demonstrating the assembly on charged substrates in a very simple and efficient way, has proven to be a reliable method to obtain structures tunable at the nanometer scale. Much effort has been put into the assembly of these structures for their use in biological applications. A number of these efforts have...