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Iron aluminides are of interest for applications in power generation from fossil fuels because of excellent high temperature oxidation-corrosion resistance in aggressive environments and are potential replacements for high temperature steels. The Fe-base composition ensures relative cheapness, while the high Al content leads to significant density reduction over commercial steels. Problems of low ductility/toughness at room temperature and poor high temperature (creep) strength, however, have prevented significant commercial use. After studies led by Oak Ridge National Laboratory (USA) from about 1980 to 2000, research has continued in Europe both as pan-European efforts and as national efforts in countries such as the Czech Republic, France, Germany and Spain. An overview of such recent activities is presented, indicating the research strategies involved, and the progress toward making iron aluminides useful engineering materials. Recent activities have targeted microstructural refinement through novel processing to improve room temperature ductility or attempted alloying additions to improve high temperature strength. Achieving the required properties remains difficult, and has led to developments of iron aluminides as cast components and as coatings. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Basicity, infrared and x-ray results are reported which show the uniquely high electron-donor effect of R3N+N− substituents. An explanation is offered in terms of theoretically calculated resonance, field and electronegativity σ substituent constants. Large values of the calculated first-order hyperpolarizabilities in the R3N+N−(CHCH)nNO2 series suggest the introduction of the R3N+N− substituents in the synthesis of push–pull conjugated structures for second-order non-linear optics. Copyright © 2000 John Wiley & Sons, Ltd.

An infrared spectroscopic study of the 1 : 1 hydrogen-bond association of amidates with both methanol and 4-fluorophenol showed that the site of complexation is the oxygen of the amidate function. However the formamidate HCON2Me3 forms a second 1 : 1 complex on the nitrogen of the amidate. The formation constants of the hydrogen-bond complexes of the amidates with the reference hydrogen-bond donor 4-FC6H4OH indicate that the amidates are stronger hydrogen-bond bases than are amides and amide vinylogues. As such, the amidates constitute the strongest carbonyl bases hitherto investigated on the hydrogen-bond basicity scale.

The electron ionization mass spectra of fourteen 4-substituted (4-X) camphors have been recorded and analyzed using metastable ion analysis and exact mass measurement. With respect to camphor, alkyl substituents changed the relative importance of different fragmentation pathways, though they did not induce new fragmentations. Substituents X connected to the camphor framework through an atom having a lone pair of electrons were generally lost as HX. Overall the fragmentation behaviour was essentially independent of the inductive substituent constant. Under chemical ionization conditions, only methane of the reagent gases produced extensive fragmentations of these compounds; isobutane, acetone and ammonia were ineffective. The nature of the fragmentations was independent of both the inductive substituent constant of the substituent X and the proton affinity and heat of formation of the corresponding neutral compound HX.

A previous report of a complex between 3-amino-6-methoxypyridine and acetone has been shown to be incorrect. The 1 H and 13 C NMR signals that were attributed to the complex have been shown to be due to the formation of a Schiff's base.

In a series of 4-substituted camphors, in which the substituent, X, varies from ethyl through hydrogen to nitro, we have shown that the enthalpies of complexation, with BF3 in dichloromethane, which cover a range of 14.5 kJ mol–1 correlate well with r > 0.99 with polar substituent constants with the sensitivity ρ*ca. 8.IR spectroscopy of the free ketones and the more polar BF3 complexes indicates that the latter are ca. 1.44 times more sensitive to substituent variation.Complexation occurs at both sites when X = OAc and only at the ketone when X = CO2Me.We rationalise the smaller sensitivity of the protons to substituent-induced 1H shift displacement when in the E-complexed form to the electron-attracting effect of complexation that leads to diminished electronic screening. The 4JH3exo–H5exo coupling is diminished by complexation which enhances hyperconjugation between the C(3)–Hσ and the carbonyl p orbitals to the detriment of back lobe C(3)–H3exo–C(5)–H5exoσ–σ overlap. A number of chemical shift and coupling correlations are reported.

The synthesis, characterisation and reactivity are reported for the title compound which is the first isolable compound of type RIF2 from an aliphatic iodide.

A controversy about the structures of five-membered ring sultones obtained by treatment of camphenes with acetic and concentrated sulfuric acids has been resolved by X-ray analysis of the sultone obtained from racemic camphene, namely, endo-3H-10,10-dimethyl-4-oxa-5-thiatricyclo[5.2,1.0 3,7 ]decan S,S-dioxide, (also known as 10-bornanesulfonic acid 2-hydroxy-γ-sultone), C 10 H 16 O 3 S. Five-membered saturated sultone rings are shown to be conformationally flexible.

Molecules of 13H-dibenzo­[a,i]­fluoren-13-one, C21H12O, strad­dle a crystallographic mirror plane and are essentially planar, with a dihedral angle of only 1.9 (1)° between the two naphtha­lene ring systems. Repulsive intramolecular C=O⋯H interactions therefore do not explain the larger distortions found in isomeric ketones.

This study presents the clinical and management problems in 81 epileptic patients attending the Queen Victoria Hospital for 98 pregnancies between 1985 and 1988. Epileptic women were found to have a 26.1% risk of seizure deterioration during pregnancy and the single most important factor for predicting seizure prognosis was the severity of epilepsy prepregnancy. There was a significant increase in the complications of vaginal bleeding, preeclampsia, and preterm delivery, compared with a control group of women. Infants of epileptic mothers had an increased incidence of low birth-weight and lower Apgar scores at 5 minutes. The congenital abnormality rate was 14.3% (9 major and 5 minor abnormalities). These results confirm that pregnant epileptic women are a high risk group.

The mass spectral fragmentations of one mono- and eight dibenzo-annelated bicyclo[2.2.2]octenes have been studied. Under electron ionization the retro-Diels-Alder (RDA) reaction was dominant and led to the formation of ionized anthracene; only in the case of the monobenzo compound was the RDA + 2 reaction more favourable. Anthracene formation was also important under chemical ionization, but protonation made other fragmentation channels possible so that chemical ionization spectra were strikingly more complicated than electron ionization spectra. © 1997 John Wiley & Sons, Ltd.

An IR spectroscopic study of the hydrogen bonding of Bu3N+N−C≡N with 4-fluorophenol showed that the site of complexation is the nitrogen of the nitrile function. THe formation constant of the 1:1 complex in CCl4 indicates that this cyanamidate is a stronger hydrogen-bond base than is any nitrile, amine or pyridine. The Bu3N+–N− group increases the basicity of the nitrile group very efficiently because of the conjugation of two lone pairs on the anionic nitrogen with the π systems of the cyano group. This conjugation is also exemplified by the very low ν(C≡N) wavenumber (2104 cm−1).

The rates of elimination of seven cycloalkyl acetates containing between 5 and 15 ring carbons have been determined in a static system over a temperature range 280–370°C and a pressure range 35–234 torr. The unimolecular reactions, carried out in the presence of the inhibitor cyclohexene, are homogeneous in seasoned vessels and follow a first-order rate law. The rate coefficients are exemplified by that found for cyclopentyl acetate: The sequence of relative rates is analogous to that found in most solution reactions of these compounds. The contribution of ring strain to energy barriers of these compounds is described.

Long range proton–proton coupling constants between H3exo and H5exo have been measured in a series of 4-substituted bornanones. Correlation between the magnitudes of 4J3exo–5exo and the inductive linear free energy σI has been obtained. 4-Substituted bornanone nitrimines exhibit diminished values of 4J3exo–5exo with respect to the parent ketone.

The first saturated aliphatic trivalent iodine diester and the rationale on which the synthesis is based are described.

Whereas methylation of N-ammonioamidates may occur on oxygen or nitrogen depending on whether the carbonyl group carries a methyl or methoxy substituent, n.m.r. spectroscopic evidence indicates that protonation occurs on nitrogen and in more acidic media dications are formed by further N- or -O-protonation.