In the present work, biobased protic ionic liquid crystal bis(2-hydroxyethyl) ammonium palmitate (DPA) has been studied as neat lubricant under linear reciprocating sliding at 75 °C, in crystalline region, and 110 above its melting point. Three different tribopairs have using AISI 52100 steel, 316L stainless steel sapphire balls against disks. Tribological results °C are agreement with pairs co...

Dependence and interaction between several operating conditions that affect the grinding process using a ball mill such as number of balls, duration, rotational speed on particle size at 80% product mass (P80) mineral liberation have been obtained in this study CCD (central composite design) response surface method (RSM). The was carried out cylindrical with diameter length 18.6 cm 21.5 cm, res...

High energy ball mills are used to grind powder material down to a particle size below one micron. Up to now, the detailed physical mechanisms of the grinding process inside the mill have not been fully understood. Hence, the design of these mills as well as their process parameters is based on empirical results. The ball mill has been simulated by discrete event simulation (DES) using typical ...

We give a unified geometric approach to some theorems about primitive elements and palindromes in free groups of rank 2. The geometric treatment gives new proofs of the theorems. This paper is dedicated to Bill Harvey on the occasion of his 65th birthday.

Tangents of plurisubharmonic functions Local properties of plurisubharmonic functions are studied by means of the notion of tangent which describes the behavior of the function near a given point. We show that there are plurisubharmonic functions with several tangents, disproving a conjecture of Reese Harvey.