ALBERT

Notes: Coexisting Ca-poor and Ca-rich pyroxenes in granulites at Cape Riche, in the Precambrian Albany-Fraser Province, Western Australia, are dominantly chemically homogeneous within individual samples, suggesting a major episode of equilibration. However, occasional grains in a few samples contain exsolved domains interpreted as relics of an earlier, higher-T assemblage. Pyroxene pairs in ten, presumably isothermal, samples from a restricted area are used to (i) assess the suitability of several versions of the two-pyroxene thermometer for application to metamorphic rocks, and (ii) determine the thermal history of the Cape Riche pyroxenes.The various versions of the two-pyroxene thermometer applied to the well-equilibrated homogeneous pyroxene grains show poor to good precision and yield mean temperatures varying widely from 683° to 893°C, in the following order of increasing T: Lindsley (1983; opx version), 683°± 11°C; Kretz (1982; KD version), 705°± 19°C; Ross & Huebner (1975), 709°± 30°C; Kretz (1982; solvus version), 735°± 24°C; Fonarev & Graphchikov (1982; opx version), 〈750°C; Lindsley (1983; cpx version), 784°± 40°C; Fonarev & Graphchikov (1982; cpx version), ~820°± 30°C; Wood & Banno (1973), 849°± 16°C; Powell (1978), 854°± 23°C; Wells (1977), 893°± 10°C. Independent T estimates, based on mafic assemblages and garnet-biotite thermometry, suggest that the major episode of metamorphism occurred at 700-800°C (P ~ 5 kbar). Therefore the Wells, Powell, Wood & Banno and Fonarev & Graphchikov (cpx) temperatures are almost certainly too high. In the absence of a more precise independent T estimate it is difficult to assess the relative merits of the results obtained from the remaining versions of the two-pyroxene thermometer, none of which can be unequivocally demonstrated to be seriously in error, though the Lindsley (opx) T is probably too low. Other significant shortcomings evident in the results include the relatively poor precision obtained from the three methods based on purely graphical representation of the augite limb of the solvus (i.e., the Ross & Huebner, Fonarev & Graphchikov (cpx) and Lindsley (cpx) versions), and the apparent dependence of derived T on Mg/Fe2+ ratio for the Powell, Wood & Banno and Lindsley (cpx) methods.For the bulk compositions of exsolved domains, the different versions of the two-pyroxene thermometer yield mean temperatures 23° to 82°C (overall mean, 65°C) higher than for homogeneous grains in the same samples. These exsolved domains are interpreted as relics of a higher-T (peak?) metamorphic assemblage, rather than an igneous precursor.

Notes: It is widely believed that large size creates problems for industrial relations and, conversely, that small size is beneficial. There has been little research relating size and workers' attitudes—this article reports the findings from a study in 24 factories in British manufacturing industry.

Notes: In this article the author assesses the difficulties facing democracy in the British Retail Co-operative Movement, with special reference to the role of employees on boards of directors.

Notes: This paper examines the relationship between the Chief Executive of a CO-operative retail society and his Board of Directors. It takes for its starting point three critical activities of the Chief Executive, i.e. the achievement of society objectives; the maintenance of the internal stability of the society and the adaptation of the society to the external environment.Two factors which influence the performance of these activities are the Chief Executive's orientation to society performance and his relationship with his Board.The Chief Executive will tend to be inward-outward in orientation. Factors affecting this will be his previous task experience and organisational experience of which two aspects are important (a) time—the length of service a t lower and middle management level and (b) structure—the degree of delegation. These will affect the Chief Executive Officer's ability to deal with uncertainty in the environment, A third influential factor will be the attitudes and expectations of his Board which will be structured by their perception of democratic control. Finally the nature of the environment will affect the Chief Executive's orientation and his flexibility.In dealing with the problems which face him the Chief Executive is influenced by his reference points, i.e. by the degree of internalisation of co-operative values, and by his beliefs about the rightness of previous decisions.His decision-making is influenced by the interaction of his beliefs and those of his Board and by the depth to which they are held. These beliefs may be seen in two parts, first, relating to the nature of co-operative enterprise and secondly, to the method by which the co-operative enterprise is controlled.Contributing to the depth of internalisation of co-operative beliefs would appear to be their social and political backgrounds. Additional factors for the Chief Executive Officer include length of service in the co-operative movement, non-co-operative experience and his commitment to :managerial values'.On the basis of the differing orientations of the persons concerned, it is possible to hypothesise the development of certain decision-making situations.

Notes: The growing number of ground-water research projects that are based primarily on potential distribution data has stimulated the development of several new types of potential measuring, instruments. The primary requirements for these instruments are longevity, precision, sensitivity, and short timelag. Ease of installation, minimum maintenance, low capital investment, and provision of a continuous record are equally desirable. Generally, available instruments will satisfy two or three, but not all of these requirements.The need for a piezometer possessing all these characteristics was encountered during a flow-system study beneath an irrigated field. A piezometer subsequently was designed which combines the sensitivity of a Kecke electrical water-level sensing device with the continuous record provided by a Stevens Type F, graphic recorder. Replacement of the standard Keck sensing “Bob” with a probe specifically designed for small diameter pipes (5/16-inch I.D.),* provides instrumentation with a short timelag. The absence of a diaphragm and strain gauges enhances longevity. The device is inexpensive, simple and easily installed. Samples of well water for chemical analysis may also be obtained from the piezometers.

Notes: Summary. Pyrazon (5-amino-4-chIoro-2-phenyl-3(2H)-pyridazinonc) labelled with tritium in the phenyl ring, was applied to both the root and shoot of seedlings of red beet (Beta vulgaris L., cultivar Detroit Dark Red I, German millet (Setatra italica J.), and tomato (Lycopersicon esculentum Mill., cultivar Heinz 1350). Of these species, red best is tolerant, millet is moderately tolerant, and tomato is susceptible to pyrazon.When the roots were exposed to 1–325 ppm 3H-pyrazon in the nutrient solution, the greatest root absorption and transiocation to the shoot was observed in tomato and the least in red beet, while millet was intermediate.Applications to the first true leaf indicated that pyrazon was absorbed by the foliage of all three but that it was not transported basipetally. The absorption and translocation studies indicated that pyrazon mi transported primarily in the xylem.A radioactive metabolite of 3H-pyrazon was detected in the shoots of red beet, but there was no evidence for its presence in the shoots of the other two species. Since this metabolite is radioactive, its structure must contain at least some altered form of the phenyl ring which contained the tritium in the parent molecule. This differentiates it from 5-amino-4-chloro-pyridazinone, the previously proposed degradation product of pyrazon, since this compound lacks the phenyl ring.On the bash of these results, it is hypothesized that pyrazon will be phytotoxic if a suffic inn mm entration of the unaltered chemical reaches the site of herbicidal action in the shoot.Migration et métabolisme de la pyrazone dans les espéces rislstantes et sensibles

Notes: Abstract In this paper, the radiation losses caused by film thickness and refractive index discontinuities in asymmetric slab waveguides are examined theoretically. A technique developed by Mahmoud and Beal for dealing with the continuous part of the radiation spectrum is used. Several numerical examples which show the radiation loss for various waveguide configurations are presented and discussed and, where appropriate, comparisons with other related work made. In the case of asymmetric thickness steps, the radiation losses are found to be appreciably higher than those computed for symmetric guides. The radiation losses for guides having the same thickness were found to decrease as the guide thickness increased. Once the TE1 mode become guided, the losses decreased rapidly. However, if the two guides had different thickness then it was found that the losses exhibited a minimum.