Let R be a quasi-order on a compact Hausdorff topological space X. We prove that if X is scattered, then R satisfies the Priestley separation axiom if and only if R is closed in the product space X × X. Furthermore, if X is not scattered, then we show that there is a quasi-order on X that is closed in X × X but does not satisfy the Priestley separation axiom. As a result, we obtain a new charac...

In this paper, we extend some results obtained by A. Amroune and B. Davvaz in [1]. More precisely, we will develop a representation theory of intuitionistic fuzzy perfect distributive lattices in the finite case. To that end, we introduce the notion of intuitionistic fuzzy perfect distributive lattices and the one of fuzzy perfect Priestley spaces. In this way, the results of A. Amroune and B. ...

A rescaling of variables changes the Priestley-Taylor parameter value in complementary relationship evaporation for optimal performance.

Early in my teaching career I became convinced that history has value in causing the student to look at chemistry in a realistic fashion. But, like classroom demonstrations, history should fulfill a teaching objective and not be used merely as entertainment. Further, history is made by human beings and lends a human interest which is lacking when only the facts of chemistry are expounded (1). M...

[1] B. Banaschewski, Über nulldimensionale Räume, Math. Nache 13 (1955) 129-140. [2] F. Borceux and J. Janelidze, Galois Theories, Cambridge University Press (2001). [3] M. Dias and M. Sobral, Descent for Priestley Spaces, Appl. Categor. Struct 14 (2006) 229-241. [4] B. A. Davey and H. A. Priestley, Introduction to Lattices and Order, Cambridge Mathematical Texbooks (1990). [5] R. Engelking and...

Carl Wilhelm Scheele (1742-1786) has an important place in the history of the discovery of respiratory gases because he was undoubtedly the first person to prepare oxygen and describe some of its properties. Despite this, his contributions have often been overshadowed by those of Joseph Priestley and Antoine Lavoisier, who also played critical roles in preparing the gas and understanding its na...