Double bond cleavage reaction of silyl enol ethers using MoO2(acac)2-tBuOOH

The double bond of various silyl enol ethers is smoothly cleaved to give carbonyl compounds by an oxidizing reagent MoO₂(acac)₂-^tBuOOH.     

Gas phase synthesis of Au clusters deposited on titanium oxide clusters and their reactivity with CO molecules

Titanium oxide clusters were formed in the gas phase by the laser ablation of a Ti rod in the presence of oxygen in a He gas. Not only stoichiometric but also nonstoichiometric titanium oxide clusters, Ti(n)O(2n+x)(+) (n = 1-22 and x = -1-3), were formed. The content of oxygen atoms depends strongly on a partial pressure of oxygen. Gold clusters, Au(m) (m = 1-4), were generated by the laser ablation, which were then deposited on Ti(n)O(2n+x) clusters. The formation of Au(m)Ti(n)O(2n+x)(+) follows electron transfer from Au(m) to Ti(n)O(2n+x)(+). The reactivity of Au(m)Ti(n)O(2n+x)(+) cluster ions with CO was examined for different m, n, and x by the mass spectrometry. It was found that Au(m) on Ti(n)O(2n-1)(+) are less reactive than those on the other Ti(n)O(2n+x)(+) (x = 0 and 1). In addition, the reactivity is highest when Au(m) (m = 1 and 3) is on the stoichiometric titanium oxide (x = 0), whereas the reactivity is also high when Au(2) is on the oxygen-rich titanium oxide (x = 1). The reactivity was found to relate to geometrical structures of Au(m)Ti(n)O(2n+x)(+), which were studied by density functional calculations.     

Modelling a baseball game to optimise pitcher substitution strategies incorporating handedness of players

^** Email: hirotsu.nobuyoshi{at}jiss.naash.go.jp^*** Email: m.wright{at}lancaster.ac.uk This paper proposes a method for identifying the optimal strategyfor substituting players in a baseball game, taking into considerationthe handedness of players, which is one of the main factorsin terms of managerial decision-making for substitution. Usinga Markov chain model, we incorporate the effect of the handednessof players by introducing the concept of the defensive earnedrun average as a measure of the defensive ability of pitchersand calibrating the batting probabilities of players dependingon their handedness. We then develop a dynamic programming formulationincluding the effect of the handedness of players. This methodis illustrated using a match based on the real line-ups of theColorado Rockies and the San Francisco Giants in the NationalLeague of Major League Baseball, especially focusing on theintroduction of a relief pitcher in consideration with his handedness.     

Fast verified computation for solutions of algebraic Riccati equations arising in transport theory

A fast algorithm for enclosing the solution of the nonsymmetric algebraic Riccati equation arising in transport theory is proposed. The equation has a special structure, which is taken into account to reduce the complexity. By exploiting the structure, the enclosing process involves only quadratic complexity under a reasonable assumption. The algorithm moreover verifies the uniqueness and minimal positiveness of the enclosed solution. Numerical results show the efficiency of the algorithm.     

Nanoalloy formation of Ta-containing trimetallic small clusters

Trimetallic cluster ions containing Ta and other metal elements were prepared in the gas phase by a triple laser-ablation technique in a controlled manner. We have measured the abundances and their thermal stabilities, using time-of-flight mass spectrometry. Taking advantage of specific abundance distribution of the trimetallic cluster ions (magic stoichiometry), relative to the distinguished stabilities, the coalescence or the segregation of Ta and the other elements in the subnanometer sized clusters was discussed. We found that Nb, W, and Mo, which are categorized as elements with a high heat of vaporization, readily coalesce with Ta, while V, Al, Co, and Pt, which are categorized as elements with a low heat of vaporization, tend to be segregated from Ta. Our experiments, along with the calculation by another research group, suggest that the binding energies of atoms are related to the coalescence or segregation of clusters in the gas phase.