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Resected lobes from patients having pre-operative pulmonary function tests were fixed by inflation with formal saline and cut into 1cm parasagittal slices. Randomly selected tissue, from the lateral two slices, was plastic embedded and sections prepared for microscopic analysis. A semi-automatic image analysis system was used to quantitate bronchiolar calibre and shape and peribronchiolar attachment number, inter-alveolar attachment distance and the amount of macroscopic emphysema. An automatic image analyser (IBAS2) was used to measure alveolar surface area per-unit volume (AWUV). Measured bronchiolar calibre (minimum diameter and measured lumen area) was not related to patient height, lung volume, pulmonary function or other morphometric variables. AWUV, mean inter-alveolar attachment distance, theoretical lumen area and bronchiolar shape were independent of patient size and lung volume, but were inter-related. A combination of low AWUV and loss of attachments profoundly affected bronchiolar shape. However, AWUV and alveolar attachment loss were not always in proportion and demonstrated different functional effects: AWUV affects carbon monoxide transfer factor whereas attachments affect the slope of phase III and forced expiratory volume with bronchiolar shape affecting closing volume. Macroscopic emphysema did not accurately reflect the extent of alveolar wall loss as identified by AWUV and showed poor correlations with pulmonary function tests. Computerised axial tomography (CT scan) exhibited a strong correlation with AWUV and can be used to assess lung density in life.

A study has been made of the aluminium-oxygen equilibrium in liquid iron by studying the reaction. Electrolytic iron in pure alumina crucibles was maintained at a constant temperature under a controlled water-vapour/hydrogen gas mixture until equilibrium was established between solid, liquid and gas phases. The melts were then quenched in a stream of hydrogen and subsequently analysed for aluminium and oxygen.