Gas-liquid chromatographic quantitation of phencyclidine.HCl in powders: collaborative study.

Six laboratories collaboratively studied a method for the quantitative gas-liquid chromatographic (GLC) determination of phencyclidine.HCl in powders. The phencyclidine.HCl and other water-soluble compounds are dissolved in dilute HCl. A portion of the aqueous solution is made weakly basic with K2HPO4, and the organic-soluble compounds are extracted in CHCl3 for the GLC determination of the phencyclidine.HCl. Eicosane (n-C20) is incorporated in the extracting CHCl3 as an internal standard. The samples collaboratively studied included samples of known phencyclidine.HCl concentration and one sample of unknown purity. Recoveries ranged from 92.1 to 104% and per cent standard deviations from 1.05 to 3.39. The method was adopted as official first action.     

THE DRY-MATTER PRODUCTION, BOTANICAL COMPOSITION, IN VITRO DIGESTIBILITY AND PROTEIN PERCENTAGE OF PASTURE LAYERS

Irrigated plots of a mixed sward of four grasses and white clover were cut to a height of 3 cm in either June, August, October, December or February. The plots cut at each commencement date were harvested when the height of growth of the pasture was either 10, 18, 25, 32, 40, 48 or 55 cm. At each harvest, the pasture was cut at 7 to 8 cm intervals down to a height of 3 cm. DM production, botanical composition, in vitro digestibility (DOM) and CP of each layer was determined. DM production declined from the lower to the upper layers for pastures shorter than 32 cm. For pastures taller than 32 cm, DM production declined from the lower to the middle layers, then increased in the upper layers, due mainly to the presence of seed heads. Maximum percentages of DOM and CP were observed for the middle layers of the pastures taller than 25 cm. For pastures shorter than 25 cm, DOM and CP percentages increased from the lower to the upper layers, for all commencement dates. The percentages of DOM and CP of each layer decreased as the height of growth increased. The percentage of DOM showed a positive correlation with the percentages of Lolium perenne, Bromus unioloides and Trifolium repens, and a negative correlation with the percentages of Paspalum dilatatum and chlorotic material. The percentage of CP showed a positive correlation with the percentages of Paspalum dilatatum, Dactylis glomerata and Trifolium repens and a negative correlation with the percentages of chlorotic material and the total of the four grasses within the pasture layers. The lower layers of the pasture produced large quantities of DM and, despite the lower in vitro digestibility of these layers, they produced more DOM than the other pasture layers. The DOM production of the pasture increased with increasing height of growth, but decreased as the commencement date was altered from winter through to the end of summer.     

A biological survey of Lord Howe Island with recommendations for the conservation of the island's wildlife

Lord Howe Island is located in the southwest Pacific Ocean about 720 km northeast of Sydney, Australia. The island was discovered in 1788, but has never had a large human population nor has it been intensively developed. It remains, therefore, in a substantially natural state and because of the high proportion of endemic species is of considerable interest to biologists. However, new development is possible and during 1971 and 1972 the Australian Museum co-ordinated a biological survey of Lord Howe. The object of the survey was to ascertain the status of the island's wildlife and to recommend ways to ensure its survival. The survey concluded that the status of most of the island's indigenous wildlife was satisfactory, but that a few species were threatened and that a number of introduced plants and animals were causing problems. Recommendations were made to control exotic species, to reserve the remaining natural vegetation and to base the tourist industry on the island's existing natural values including its wildlife.