A comprehensive product study, performed via the turbulent flow chemical ionization mass spectrometry (TF-CIMS) technique, of the primary OH-initiated oxidation of many of the atmospherically abundant aromatic compounds was performed. The bicyclic peroxy radical intermediate, a key proposed intermediate species in the Master Chemical Mechanism (MCM) for the atmospheric oxidation of aromatics, w...

We construct an efficient randomized algorithm that, given a digraph, tests if it is a strongly connected graph. And the query complexity of our algorithm is polylogarithmic in the size of the digraph.

Let H be a digraph possibly with loops and let D be a digraph whose arcs are colored with the vertices of H (an H-colored digraph). A walk (path) P in D will be called an H-restricted walk (path) if the colors displayed on the arcs of P form a walk in H. An H-restricted kernel N is a set of vertices of D such that for every two different vertices in N there is no H-restricted path in D joining ...

A k-geodetic digraph G is a digraph in which, for every pair of vertices u and v (not necessarily distinct), there is at most one walk of length ≤ k from u to v. If the diameter of G is k, we say that G is strongly geodetic. Let N(d, k) be the smallest possible order for a k-geodetic digraph of minimum out-degree d, then N(d, k) ≥ 1 + d+ d2 + . . .+ dk = M(d, k), where M(d, k) is the Moore boun...

It is known that the spectral radius of a digraph with k edges is ≤ √ k, and that this inequality is strict except when k is a perfect square. For k = m + l, l fixed, m large, Friedland showed that the optimal digraph is obtained from the complete digraph onm vertices by adding one extra vertex, and a corresponding loop, and then connecting it to the first ⌊l/2⌋ vertices by pairs of directed ed...

This contribution describes the synthesis of several novel bicyclic α-amino endoperoxides, including CF(3)-substituted compounds, prepared by the aerobic electrochemical oxidation of a family of bicyclic aminocyclopropanes. These, in turn, are readily synthesised by a titanium-mediated intramolecular cyclopropanation process (Kulinkovich-de Meijere reaction), starting from N-alkenyl amides that...