HighlightsWe present the first results from a new 60 MHz 1H NMR bench-top spectrometer.Using chemometrics, we detected hazelnut oil adulteration of olive oil at 11.2%w/w.Bench-top 60 MHz NMR performs at least as well as FTIR for this type of application.

A high temperature solution processing method was adapted to prepare durable, freestanding, submicrometer thickness films for transmission infrared spectroscopy studies of ionomer membrane. The materials retain structural integrity following cleaning and ion-exchange steps in boiling solutions, similar to a commercial fuel cell membrane. Unlike commercial membrane, which typically has thicknesses of >25 μm, the structural properties of the submicrometer thickness materials can be probed in mid-infrared spectral measurements with the use of transmission sampling. Relative to the infrared attenuated total reflection (ATR) technique, transmission measurements can sample ionomer membrane materials more uniformly and suffer less distortion from optical effects. Spectra are reported for thermally processed Nafion and related perfluoroalkyl ionomer materials containing phosphonate and phosphinate moieties substituted for the sulfonate end group on the side chain. Band assignments for complex or unexpected features are aided by density functional theory (DFT) calculations.

A method is described for plotting and comparing measurements made on kaolinite clays. In this the ratio of the two strongest bands in the OH-stretch region of the spectrum (band maxima at 3695–3700 cm−1 and 3620–3625 cm−1) of an oriented preparation at 45° incidence is plotted against the corresponding ratio from the spectrum of a randomly oriented preparation. Both ratios are affected by the shape of the kaolinite particles and methods for minimizing this are given. The position of a kaolinite upon a plot so prepared gives information on the following points: (a) the type of kaolinite, (b) the degree of crystallinity of the kaolinite, (c) the shape of the kaolinite particles.

The study reported in Part I has been extended in the present Part by grinding a kaolinite for a total of 1000 hours and withdrawing samples at intervals. The samples were examined by all the tests of Part I (except heat of immersion) as well as by a number of additional tests, among which the most important were thermogravimetric analysis and X‐ray diffraction. The thermogravimetric results show that the lattice is progressively distorted as grinding progresses, but that its chemical composition is unchanged. The specific surface measured by nitrogen sorption increases by some fourfold up to a maximum at 600 hours or so, and then drops to approximately threefold the original value at 1000 hours. Comparison of results for nitrogen sorption and for particle‐size distribution—by sedimentation in water (Andreasen test)—shows that aggregates possessing a considerable internal area are progressively produced by the grinding. The distortion of the lattice and the increase in specific surface each causes a marked increase in the solubility of the ground solid in hydrochloric acid. Both the base‐exchange capacity and the content of adsorbed water (which is driven off at 100°) increase fairly continuously with the time of grinding. The results of this Part thus confirm and extend the conclusions of Part I.

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Two samples of refined Devon china clay have been ground for 94 and 120 hours respectively. The specific surface (as measured by gas sorption), the heat of immersion in carbon tetrachloride and the base‐exchange capacity all increased appreciably, but the content of ‘structural’ water was scarcely affected; the density in carbon tetrachloride fell. Grinding probably breaks up the particles and distorts, but does not destroy, the lattice of the kaolinite.

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