Wyoming bentonite, exchanged with cations of high charge density, is an efficient and selective catalyst for the production of ethyl acetate, in a single step, from ethylene and acetic acid. The reaction occurs in the interlamellar space of the clay where it is proposed that strong Brönsted acid sites on the clay coupled with highly polarized intercalated reactants produce a reaction which is otherwise difficult to carry out.

Ion-exchanged montmorillonites behave as solid acid catalysts and are effective and selective catalysts for the hydration of ethylene. The reaction proceeds predominantly in the interlamellar environment of the clay catalyst. Ethylene conversions were found to be markedly dependent on the choice of exchangeable cation, with Al being the best of those examined.

Ion-neutral chemistry in Titan's upper atmosphere (~ 1000 km altitude) is an unexpectedly prodigious source of hydrocarbon-nitrile compounds. We report observations from the Cassini Ion Neutral Mass Spectrometer (INMS; Waite et al. 2004) and Cassini Plasma Spectrometer (CAPS; Young et al. 2004) that allow us to follow the formation of the organic material from the initial ionization and dissociation of nitrogen and methane driven by several free energy sources (extreme ultraviolet radiation and energetic ions and electrons) to the formation of negative ions with masses exceeding 10,000 amu.

Of all the leading personalities who left their imprint on the history of the Peloponnesian war Tissaphernes was to Thucydides the most enigmatic. Although judgements on the ability and character of individuals occur more frequently in the eighth book of the History than in other parts, Thucydides apparently did not feel himself to be in a position to include an explicit judgement on Tissaphernes. Nor does Tissaphernes, unlike many major and minor characters, receive even a brief descriptive introduction, though such introductions are also exceptionally plentiful in the eighth book. Thucydides has been successful in collecting an abundance of detailed information about the part played by Tissaphernes in the opening phase of the Ionian war and yet has failed to produce a satisfactory picture of him. In this paper attention will first be drawn to special problems arising in the case of Tissaphernes which do not arise in the presentation of other leading characters. My main purpose, however, is to attempt to establish that the account of him by Thucydides is basically inconsistent and that this inconsistency occurs because the material in the eighth book has not been fully integrated.

One source of difficulty for Thucydides in writing about Tissaphernes was that he seems to have had little opportunity to acquire knowledge of Persia and the Persians. There is no indication that he spent any part of his exile in or near Asia, and the notorious sparsity of his references to Greek relations with the Persians before the outbreak of the Ionian war suggests that his contacts with them were scanty. In this respect he was not exceptional. Before the end of the fifth century even the best educated Athenians seem to have possessed only a dim or distorted impression of Persia, as is illustrated in different ways by the Persae and the Acharnians.