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Blasius perturbation solutions are developed for the incompressible laminar boundary layer at high Schmidt numbers. The eigenvalues have been found to be multiples of 3/2 and the eigenfunctions can be expressed as confluent hypergeometric functions. The eigenfunctions are employed in analyzing a continuous desalination system. The reverse-osmosis boundary condition leads to an integral equation which is, in turn, solved by iterative techniques. The first-order calculations show that the results are most accurate for large ratios of osmotic to applied pressures. For medium ratios, the results are reasonably good.

Four layers, a dust layer, an anorthosite layer, a basalt layer and a dunite layer, have been used to model the surface of the Moon 4·6 billion years ago. The equations describing heat conduction with or without radioactive heating have been written and Laplace transform techniques have been applied. The thermal history of the imbedded basalt-like material has been found by numerical inversion of the Laplace transform. The objective of the present analysis is to determine whether the solidification of the basalt could be delayed about 1 billion years to produce the observed age difference between the dust and the crystalline rocks found on the surface of the Moon.

Nonlinear programming techniques are frequently used to design optimum monitoring networks. These mathematically rigorous techniques are difficult to implement or cumbersome when considering other design criteria. This paper presents a more pragmatic approach to the design of an optimal monitoring network to estimate human exposure to hazardous air pollutants. In this approach, an air quality simulation model is used to produce representative air quality patterns, which are then combined with population patterns to obtain typical exposure patterns. These combined patterns are used to determine ‘figures of merit’ for each potential monitoring site, which are used to identify and rank the most favorable sites. The spatial covariance structure of the air quality patterns is used to draw a ‘sphere of influence’ around each site to identify and eliminate redundant monitoring sites. This procedure determines the minimum number of sites required to achieve the desired spatial coverage. This methodology was used to design an optimal ambient air monitoring network for assessing population exposure to hazardous pollutants in the southeastern Ohio River valley.

In Part I a model for predicting the dynamic behavior of photochemical air pollution was formulated. To exercise the model, pollutant emissions must be specified as a function of time and location over the region of interest. In this paper (Part II) we present a general methodology for the compilation of a contaminant emissions inventory for an urban area. Particular attention is given to the description of motor vehicle emissions, which constitute the most important single source of pollutants in the region to which the model is applied, the Los Angeles airshed. The model is used to estimate the spatial and temporal distribution of carbon monoxide, hydrocarbon, and nitrogen oxide emissions in the Los Angeles airshed in Autumn 1969.

The inductive and repressive actions of the plant growth hormone, indole-3-acetic acid (IAA) on a peroxidase-based enzyme system which may control endogenous levels of IAA have been described in detail (Galston, Lavee & Siegel, 1968). In this paper we show that the repressive effect of IAA may be duplicated by a macromolecular fraction extracted from the tissue. Such a fraction may be under the direct control of IAA, and could represent the mechanism through which the hormone affects the enzyme activity.