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The performance of a few typical Loeb-Sourirajan type porous cellulose acetate membranes is reported for the treatment of hard, polluted, and sewage waters. The membranes used are specified in terms of pure water permeability constant and solute transport parameter for sodium chloride. Using feed waters containing 300- to 800-p.p.m. hardness (expressed as CaCO3), product waters containing 2 p.p.m. or less could be obtained with 90% product recovery and an average initial flux of 38 gallons per day per sq. foot at 1000 p.s.i.g. The possibility of producing 'ultrapure' waters by repeated reverse osmosis processing is indicated. The separation of common pollutants such as nitrates, borates, fluoride, alkyl benzene sulfonate (ABS), ammonia, and phosphates, and a few others usually present in plating wastes, and the applicability of the reverse osmosis process for the treatment of sewage waters and water renovation are illustrated. (Author)

A method for analyzing total airborne barium for analysis by absorption spectrometry is described. The reducing potential of filter paper on barium sulfate is used to reduce quantitatively the insoluble barium compound to acid soluble barium sulfide. -- AATA

An economic air pollution control model is formulated for determining the least cost of reaching various air quality levels. The model takes the form of a general, nonlinear, mathematical programming problem. The two basic inputs to this model are the least cost of attaining various emission levels and the relationship between emission levels and air quality. A linear programming submodel is presented for deriving the first input, the control cost-emission level relationship. Empirical-statistical air quality submodels are outlined for obtaining the second input, the emission level-air quality relationship. The combination of these two inputs to solve the nonlinear programming problem is illustrated graphically. Part II of this paper (page 816) applies the model to photochemical smog in Los Angeles in 1975.

The particulate matter entitted from present-day cars is a complex mixture of inorganic salts, soot and carbonaceous material. Measurement and characterization of such particles require elaborate sampling systems and sophisticated analytical techniques. This paper is a review of the major contributions in this area. A number of systems suitable for sampling and characterization of the exhaust particles are described. Also included is a wide selection of data from a number of workers that, in the author's opinion, best represent the state of the art. /Author/

~~~~ The crude oil content of marine sediments was determined by ir spectrometry from the magnitude of 2925 cm-1 (-CHzstretching band) absorbance. Biological materials also absorb at 2925 cm-I and have a well-defined absorbance band at 1650 cm-1 (the -NH- band characteristic of proteins) whereas, crude oils do not exhibit an amide band. The relative contributions of oil and organic material of recent biological origin in marine sediments were determined from measurements of these two absorbance bands, and a correction applied which enables the calculation of the oil content in the presence of these biological materials. n a recent study of the effects of the winter 1969 oil blowI out at Platform A in the Santa Barbara Channel, analytical procedures for the rapid determination of the oil content of the channel bottom sediments using both transmission and internal reflectance ir spectrometry were reported (Mattson et al., 1970b; Kolpack et al., 1971; Yu et al., 1971). In these analyses, the oil content of the sediment wdS considered to be related to the magnitude of the 2925 cm-1 (-CHzstretching band) absorbance. Those analyses were made primarily on bottom sediments which were deposited following a major flood. The rate of sedimentation of this highly oxidized detrital flood material was very rapid and in most samples there were no significant amounts of organic material of recent biological origin present. However, some of the samples were obtained from the central part of the Santa Barbara Channel up to 18 months after the flood. The rate of detrital sedimentation in this area is much slower, and the surficial sediments often were mixed with organic debris of biological origin. The presence of biological material interfered with the determination of the oil content as the -CH*- groups of such biological matter also absorb at 2925 cm-l. This ir band is identical for any -CHz--containing compound, and the relative contributions of oil and biological matter to the observed absorbance cannot be determined by a simple measurement of the 2925 cm-l band. This paper reports a simple extension of the above ir procedure which permits estimation of the concentration of biological materials. This provides a method for correcting the 2925 cm-1 absorbance band to enable the estimation of the oil contribution alone.

A paper by Schuck and Locke is discussed and evaluated. The author's conclusions are that the authors presented good evidence supporting their thesis that particulate lead from automobile exhaust contaminates crops growing in the vicinity of high traffic density roadways. Their contention that this contamination is entirely a surface coating is not well substantiated. Some of the results are inconclusive and others suggest a surface adsorption or the absorption of some lead into the plant parts studied. The possibility of the uptake of lead from soils is not eliminated. Soil lead levels in the vicinity of high traffic density highways could eventually become of concern. Although lead appears to be immobile in the soils, some work suggests that the lead does become available to some crops at certain high concentrations.