Although studies of the composition of alveolar air have been invaluable to the advance of respiratory physiology a precise definition of alveolar gas pressures and the accurate sampling of alveolar air have proved elusive goals (1). Owing to the cyclic nature of the ventilatory process the partial pressures of 02 and CO2 in the alveoli are changing continually (time factor) (9), and, owing to ...

Although studies of the composition of alveolar air have been invaluable to the advance of respiratory physiology a precise definition of alveolar gas pressures and the accurate sampling of alveolar air have proved elusive goals (1). Owing to the cyclic nature of the ventilatory process the partial pressures of 02 and CO2 in the alveoli are changing continually (time factor) (9), and, owing to ...

A fully automated system for the determination of δC and δO in atmospheric CO has been developed. CO is extracted from an air sample and converted into carbon dioxide (CO2) using the Schütze reagent. The isotopic composition is determined with an isotope-ratio mass spectrometer (IRMS) technique. The entire system is continuously flushed with high-purity helium (He), the carrier gas. The blank s...

There is currently scarce information on the occurrence and distributions of Polycyclic Aromatic Hydrocarbons (PAHs) in the air from industrial estates in Nigeria. Hence, the present study aims to evaluate the extent and sources of pollution of polycyclic aromatic hydrocarbons in the air from some industrial estates in Lagos and Ogun States, Nigeria. Ten air samples have been collected from the...

The Bi-Air (BA) dual-trace 25 mm filter cassette was described, and its performance for the collection of Aspergillus/Penicillium (Asp/Pen) and Stachybotrys type spores in a clam-air settling chamber was compared to that of the Air-O-Cell (AOC) cassette. The BA produced duplicate sample traces, the sample traces were confined to two small, welldefined areas on the filter, and the small size of ...

Mn–Zn ferrite powders (Mn0.5Zn0.5Fe2O4) were prepared by the nitrate–citrate auto-combustion method and subsequently annealed in air or argon. The effects of heat treatment temperature on crystalline phases formation, microstructure and magnetic properties of Mn–Zn ferrite were investigated by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning electron microscopy a...