A partially ordered set (X, is called sharply transitive if its automorphism group is sharply transitive on X, that is, it is transitive and the stabilizer of every element is triviaL It is shownâ€¦ (More)

For a graph 9 let F(r be the class of finite graphs which do not contain an induced subgraph isomorphic to q~. We show that whenever q~ is not isomorphic to a path ont~t most 4 vertices or to theâ€¦ (More)

There are a number of results which, for some class of combinatorial structures, give a classfication of those members that satisfy certain homogeneity conditions. Countable ordered sets with theâ€¦ (More)

Waste management & research : the journal of theâ€¦

2007

The volcanic soils of southern Chile have demonstrated a high capacity to adsorb environmental pollutants, but for an industrial application, a stable solid material is necessary. The objective ofâ€¦ (More)