ALBERT

Description: This paper describes the results of further experimental investigation of the turbulent boundary layer with zero pressure gradient. Measurements of autocorrelation and of space-time double correlation have been made respectively with single hot-wires and with two hot-wires with the separation vector in any direction. Space-time correlations reach a maximum for some optimum delay. In the case of two points set on a line orthogonal to the plate, the optimum delay Ti is not zero. In the general case it is equal to the corresponding delay Ti, increased by compensating delay for translation with the mean flow. Taylor's hypothesis may be applied to the boundary layer at distances from the wall greater than 3% of the layer thickness. Space-time isocorrelation surfaces obtained with optimum delay have a large aspect ratio in the mean flow direction, even if they are relative to a point close to the wall (0·03δ); the correlations along the mean flow then retain high values on account of the large scale of the turbulence. © 1958, Cambridge University Press. All rights reserved.

Description: The C14 measurements reported here were carried out by the Radiocarbon Laboratory, Dept. of Geophysics and Geochemistry, A.N.U., between Jan. and Aug. 1967. Laboratory equipment consists of a Beckman methane gas-proportional unit (ANU I) supplemented in Dec. 1966 by an automatic 3-channel Beckman model LS-200 liquid scintillation spectrometer. Synthesis of methane and benzene is the same as used in ANU I and described by Polach and Stipp (1967). Treatment of samples remains a 2N hot acid (HCl) wash unless otherwise specified. Where applicable, fractional separation follows procedures reported by Olson (1963), Berger et al. (1964), Tamers and Pearson (1965), and Krueger (1966). In the treatment of bone samples, physical or mechanical cleaning could not completely remove sedimentary material often filling the structural pores. This material, if present, was retained with the fraction referred to as “collagen”. Since we are not dealing with pure collagen, we prefer to call it “acid-insoluble” bone fraction, a name describing the treatment. These dates are reported as equal to or greater than given age. Table 1 summarizes all dated fractions.

Description: The Radiocarbon Dating Laboratory is installed in the Department of Geophysics and Geochemistry, Institute of Advanced Studies of the Australian National University. The Australian Institute of Aboriginal Studies has materially aided the establishment of the laboratory and is allocated a major proportion of the dating time over the next three years for samples in Australian Aboriginal archaeology. Beyond this the laboratory is to serve research needs within the University. To facilitate communication between collectors and laboratory a handbook on collection of specimens and interpretation of results has been prepared (Polach and Golson, 1966) and a radiocarbon sample record and an age determination sheet are in use.

Description: 1. Fifty-one experiments on the nitrogen, phosphate and potash requirements of maincrop potatoes were carried out in Great Britain in 1956–62. Each experiment tested four rates of each nutrient in all combinations and both total and riddled yields and quality data were obtained.2. Nitrogen requirement was influenced by previous cropping and the rainfall during the preceding winter. 50–80 lb/acre of N are recommended in mixed farming rotations depending on winter rainfall, and 120–150 lb/acre of N in arable rotations.3. Yield increases from phosphate were usually larger on soils with low citric-soluble phosphate. Nevertheless, irrespective of soil phosphate status, optimum rates of application were at least 120 lb/acre of P2O5 which was the highest rate tested in most of the experiments.

Description: The paper refers to a number of areas in which the lineations are related to major folds. It shows that the shapes of individual folds, the interference of neighbouring folds, and the imposition of a second generation of folds all influence the arrangement of linear structures and that lineation maps may only become explicable when the major structure has been determined.

Description: This paper describes the results of an experimental investigation of the turbulent boundary layer on a flat plate with zero pressure gradient, carried out at the Laboratoire de Mécanique de l'Atmosphère (I. M. F. Marseille). Transition to turbulent flow was obtained either by increasing the preturbulence upstream of the plate by means of a grid, or by a series of emery paper roughness elements beginning at the leading edge. The measurements were of the space-time double correlations, i.e. double velocity correlations with both spatial separation and time delay, from which isocorrelation lines for optimum delay can be drawn, and of the spectrum function, all for the longitudinal component of the velocity fluctuation.

Description: SUMMARY1. Pot and field experiments were made to compare the effects of thiosulphates and sulphur on the incidence of manganese deficiency in oat, beet and pea grown in two manganese-deficient soils.2. The addition of sodium or calcium thiosulphate to oat plants growing in a manganese-deficient fen soil in boxes markedly reduced symptoms of ‘grey speck’ and increased the soluble manganese content in the leaf tissues, but the effect was transient.3. The growth of beet in this soil in clay pots was improved by the addition of thiosulphates, and also by painting the exterior of the pots with bitumen paint or by covering the surface of the soil with a thin layer of sand. The thiosulphate treatments increased the manganese uptake by the plants and reduced the symptoms of manganese deficiency, particularly when applied to pots painted with bitumen paint.4. Field experiments with an old garden soil deficient in manganese showed that thiosulphate treatments increased the manganese uptake of beet. Placement treatments were more effective than broadcast treatments and greatly improved the growth of beet and reduced or eliminated manganese-deficiency symptoms, without producing any change in soil pH.

Description: The second European Mechanics Colloquium, on the subject of three-dimensional boundary layers, was held at Liverpool University from 4 to 7 January 1966 and was attended by thirty-eight people closely associated with current work in this field.The meeting was opened by an introductory review by J. C. Cooke, who successfully sought to provoke discussion by emphasizing areas of apparent agreement and disagreement. The discussions which followed were based on a series of contributions by participants in the Colloquium, and covered the following topics:Laminar boundary layers.Three-dimensional perturbations of two-dimensional turbulent boundary layers.Corner and secondary flows.Boundary layers associated with flow past obstacles.Flow over delta wings.Separation.Flow over rotating surfaces.Heat and mass transfer.Miscellaneous topics.In all these cases, the emphasis was on the three-dimensional nature of the flow, and in this report the discussions are summarized under these headings.

Description: 1. In five experiments, groups of milking cows were changed abruptly from winter-stall feeding to graze a number of different swards, and changes in the concentration of blood-serum magnesium and of other blood constituents have been studied.2. Wide variations in the severity of hypomagnesaemia in individual cattle were found in all experimental groups, due possibly to such factors as individual variations in the intake of herbage, the requirement and body reserves of magnesium and the capacity to absorb magnesium from the gut.3. The degree of hypomagnesaemia observed was independent of the level of milk production, but was generally less severe in Friesian than in Shorthorn and Guernsey cattle. The onset of hypomagnesaemia was delayed for a few days in cattle with a high serum-magnesium concentration at the commencement of grazing.4. In two out of three experiments in which the effect of fertilizer treatment was studied, the incidence and severity of hypomagnesaemia was increased by the application to the sward of heavy dressings of nitrogenous fertilizer. In the third experiment, severe hypomagnesaemia occurred on a plot which had received no nitrogen fertilizer, due, it is thought, to a restricted intake of herbage magnesium, since the sward was extremely sparse. The feeding of supplements of flaked maize, crushed barley, crushed dredge corn, molassed sugar-beet pulp or a concentrate mixture balanced for milk production, to grazing cattle did not reduce the incidence of hypomagnesaemia.5. The cutting of grass and feeding it in the stall did not prevent the development of hypomagnesaemia.6. Blood pH and the concentrations of bloodserum calcium, sodium, potassium and blood glucose in cattle were unaffected by a change from winter feed to spring grazing, but a marked change in blood-serum non-protein and urea nitrogen and blood ammonia nitrogen, but not in any other nitrogenous constituents of the serum, was observed. The concentrations of serum non-protein and urea nitrogen and blood ammonia nitrogen were highest in groups of cattle grazing swards which had received a heavy dressing of nitrogen fertilizer and had a high nitrogen content.7. In the two experiments in which the severity of hypomagnesaemia was increased by the application of nitrogenous fertilizer, there was a close group association between high concentrations of blood serum non-protein and urea nitrogen and blood ammonia and low concentrations of blood-serum magnesium. High levels of serum urea and blood ammonia during grazing are thought to reflect a high ammonia production in the gut, which may be responsible for the disturbance in magnesium metabolism which produces hypomagnesaemia.

Description: SUMMARYEwo milk yield data obtained by the lamb suckling technique from nutritional experiments were analysed statistically to obtain estimates of the several components of variation. Diurnal variation was studied. The fitting of a sinusoidal curve removed a significant amount of variation.There was a highly significant correlation between successive milk yields obtained at 4 h intervals. Number of lambs suckled and body weight of ewe at parturition had a significant effect on total daily milk yield.The variation within ewes after the removal of diurnal variation and between ewes after the removal of the effects of number of lambs suckled and body weight at parturition were computed. These sources of variation were combined in a general equation which enabled the prediction of the standard errors associated with daily milk production for a given sampling technique. The practical application of the predicted standard errors is discussed.