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The objective of the research has been to develop a series of latentiated radiation protectives with the hope of producing one or more agents which may be of practical use in man.

The rate of reaction of F atoms with a series of compounds, CH4, CH3F, CH2F2, CHF3, CHClF2, HCl, CBrF3, NH3, and PH3 has been determined relative to the chemiluminescent reaction F + NO + Ar to FNO* + Ar to FNO + Ar + hv by photometry. The fluorine atoms were produced in a flow system from the fluid mixing of molecular fluorine and nitric oxide diluted with argon. (Author)

The FCO radical has been produced by flash photolysis of a mixture of N2F4, CO and N2. The absorption spectrum of FCO exists for approximately 50 microsec after the photolysis flash. The spectrum has an extensive series of bands between 2200 and 3400 A. The principal progression appears to have a spacing of approximately 650/cm. A possible reaction mechanism for the production of FCO is proposed. (Author)

The electrophoretic patterns, optimum pH, substrate specificity, Km values, rates of substrate hydrolysis and sensitivity to inhibition by (DFP) Disopropylfluorophosphate, paraoxon and (DDVP) dichlorvos were compared for the plasma pseudocholinesterases of the horse, man, mouse, guinea pig, dog, cat, rat, rabbit, swine, goat and hamster. The molecular heterogeneity of these enzymes was established. There were no significant differences in activity between sexes of the same species, except in the rat where the female had 4- to 10-fold higher activity than the male. Data presented as I50 values for the anticholinesterases showed that DFP was the most potent, paraoxon and DDVP being 10-fold and 100-fold less potent, respectively. With the exception of the rabbit, goat, hamster and swine, which were very resistant to DFP the inhibitor I50 values were quite similar despite the marked species variations in enzyme activity and specificity. (Author)

Various techniques including electrophoresis, gel filtration, and titrimetric and spectrophotometric analysis with specific and nonspecific substrates and inhibitors were used to characterize the serum esterases of male and female dogs. Electrophoresis in starch gel yielded 10 distinct bands of activity: four butyrylcholinesterase bands, an esterolytically active albumin, and five bands of aliesterase and/or arylesterase activity. Gel filtration on Sephadex G-200 yielded two distinct peaks of activity, one containing the cholinesterase bands, and the second peak containing both arylesterase and aliesterase activity in close association with the serum albumin. Kinetic characteristics determined for the canine serum esterases included (1) optimal pH; (2) Km values for esters of choline, alpha-naphthol, and p-nitrophenol; and (3) average rates of hydrolysis of alpha-naphthyl acetate, butyrylcholine iodide, p-nitrophenyl acetate, and E600 by the sera of males and females. The sensitivity of the serum esterases to inhibition by various cations, and specific and nonspecific inhibitors was investigated. The organophosphate, E600, may be a highly specific substrate for the detection and quantification of arylesterase in a mixture of nonspecific carboxylesterases. (Author)

Pub. in Fisheries Research Board. Journal (Canada) v21 n3 1964 (Copies available only to DDC users).

John von Neumann's idea of sampling from a distribution by majorizing its probability density function is applied to gamma and beta distributions. Optimum envelopes are constructed resulting in sampling algorithms whose performance will not deteriorate when the parameters are increased. In some methods the process of acceptance is accelerated. For this the employed test functions are replaced in most cases with simpler bounds which are difficult to derive but easy to apply. The reported computational experience indicates that the new methods can be of considerable practical use. (Author), Prepared in cooperation with Nova Scotia Technical Coll., Halifax, and Dalhousie Univ., Halifax. (Nova Scotia).

NMR spectroscopic evidence has shown that adrenolutin (5,6-dihydroxy-N-methylindoxyl) exists in the ketonic, rather than in trihydroxyindole form in solution. (Author), Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia). Dept. of Chemistry.

The Hohenberg-Kohn-Sham gradient expansion of the correlation and exchange potential for an electron gas has been investigated at metallic densities. To fourth order, the authors have evaluated the coefficients, corresponding to linear response theory, from recent calculations of the dielectric function. It was found that these coefficients show a substantial density variation. The results also show that, for rapidly varying external potentials, better estimates are obtained for the charge density by using the local density approximation than by truncating the gradient expansion at low order. (Author), Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia). Dept. of Physics.

Several spots are often detected on chromatograms obtained from solutions of a single pure beta-(3,4-dihydroxyphenyl)ethanolamine derivative, such as adrenaline, particularly when the base is dissolved in strong acids prior to chromatography. The formation of some of these multiple spots can be explained by either the formation of complexes or salts, involving the catecholamine and the acids employed, or by the chemical modification of the catecholamine prior to chromatography. It has now been shown that substances responsible for certain artifact spots are formed by the interaction of one of the components of the chromatographic solvent system used with a reactive intermediate derived from the beta-phenylethanolamine derivative being chromatographed. For example, adrenaline n-butyl ether is formed during the chromatography of adrenaline in n-butanol-hydrochloric acid solvent mixtures and beta-(p-hydroxyphenyl)-beta-(3',4'-dihydroxyphenyl)ethylmethylamine is one of the artifact spots observed when adrenaline is chromatographed in phenol-hydrochloric acid systems. (Author), Prepared in cooperation with Dalhousie Univ., Halifax, Nova Scotia (Canada). Dept. of Chemistry.

The trimethylsilyl derivatives of the anions SiO4(4-), Si207(6-), Si309(6-), Si3O10(8-) and Si4O12(8-) were resolved below 290C on SE-30 (methylpolysiloxane) liquid phase using a temperature-programmed operation and were identified by high-resolution mass spectrometry. The cracking pattern of these derivatives in the mass spectrometer is discussed. (Author), Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia), Dept. of Chemistry.

This paper presents a survey of chance-constrained programming results and applications. It begins with a detailed discussion of the basic concepts involved in chance-constrained programming. This discussion is followed by a summary of results which have been established for a variety of chance-constrained models. Then a survey of applications is considered. Here the applicability of chance-constrained models to problems in financial planning and competitive decision making is emphasized., Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia). Presented at the International Symposium on Mathematical Programming, Princeton Univ., N. J., 15 Aug 67.

The paper is concerned with the development of a model for planning shipping prices over various routes of a transportation network. It is assumed that over each route a 'railroad' (or other transport firm) competes directly with one other shipping firm (e.g., another railroad, a trucker) for the volume of business which is to be shipped over the route. We allow the possibility that the railroad's competition will come from different firms over different routes. The main assumptions of the model are the following: (a) over each route, each of the two competing firms has a group of 'hard core' customers which it will keep as long as it does not radically change its shipping price; (b) over each route there is a variable random demand of known distribution whose parameters may be price dependent, arising from a group of customers which assigns the bulk of its business to the firm charging the lowest price. The model we consider is a multi-route problem which involves both institutional and physical operating constraints. Since each competing firm sets its price policy independently and before the variable demand is known, some of these constraints cannot be guaranteed to hold with certainty. Thus they are best expressed as chance constraints. The objective of the 'railroad' is to maximize its profit subject to the constraints of the model. The solution of the model synthesizes a pricing policy for the 'railroad;' we also indicate how variations of the model can be employed in a sensitivity analysis of the suggested policy and discuss the relationship between our model and other notions in game theory and chance-constrained games., Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia). Prepared for presentation at the International Symposium on Railroad Cybernetics (2nd), Canada, October 1-6, 1967.

For some years research on solution theorems in probabilistic programming has been dormant. The obvious consequences of formal similarities to deterministic mathematical programming problems had been rapidly exhausted by researchers. Currently, however, the deeper study which was taking place during the 'dormant period' has begun to produce results. On the one hand theorems characterizing optimal classes of stochastic decision rules for various general change-constrained problems have been obtained. On the other hand, a great amount of effort has been expended on the special class of problems called linear programming problems under uncertainty, usually 2-stage and under still more special assumptions. The general objective of these specializations has been to attain results and thereby to gain insight and technique to reapproach more fruitfully the more important and general but more recondite probabilistic programming problems. To this end, few abstractions or devices, from finite-dimensional Banach spaces to the Kakutani fixed-point theorem appear to have gone untried, except, perhaps, the ancient one of study and correlation of the existent results of other researchers. It is the purpose of this paper to provide some such correlation and a redirection so that these simpler probabilistic programming problems may be overcome in all generality with new, simpler methods which offer some promise of extension to the more involved chance constrained (and other probabilistic) models., Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia), and Texas Univ., Austin.

The paper is directed at the investigation of relationships of chance-constrained programming to problems in game theory. The model introduced and analyzed herein is a two-person game model with zero-sum payoff matrix in which the strategies selected by the players do not in themselves determine the payoffs, but in which random perturbations with known distributions modify the strategy of each player before actual implementation of the strategies. A major hypothesis is that, while the strategy perturbations may be random vectors with known distributions, the selection of strategies (or more accurately strategy policies) is to be made before any observations of the random variables are made so that the strategies chosen are to be 'zero-order' decision functions of the random perturbations, in the customary terminology of chance-constrained programming. The strategy selected by each player is to be chosen to extremize that payoff which the player can be assured with at least some (a priori specified) probability. The point of departure in formulation and analysis of the model is a chance-constrained version of the two dual linear-programming problems which characterize an ordinary zero-sum two-person game. A key result shows that the deterministic equivalents for these problems yield an equivalent deterministic two-person game which is not zero-sum, and that a pair of optimal strategies for the original game are given by an equilibrium point for the latter. (Author), Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia). Prepared for presentation at the Econometric Society Annual Meeting, San Francisco, December 1966.

The decomposition of the carbamate insecticides carbaryl (1-naphthyl-N-methylcarbamate) and Mobam (4-benzothienyl-N-methylcarbamate) and the herbicides IPC ((isopropyl)-N-phenylcarbamate) and CIPC ((isopropyl-N-13-chlorophenyl) carbamate) in water at various pH's was investigated. Analyses were performed in situ on silica-gel thin-layer chromatograms by reflectance spectroscopy after the developed chromatograms had been sprayed with the reagent CNTNF (9-dicyanomethylene-2,4,7-, trinitrofluorene) to form visible pi-complexes of the pesticides. Carbaryl and Mobam decomposed rapidly at basic pH's but were stable in acid. IPC and CIPC were stable in water at pH's tested. (Author), Prepared in cooperation with Dalhousie Univ., Halifax (Nova Scotia). Dept. of Chemistry. Presented at the Symposium on Recent Advances in the Analytical Chemistry of Pollutants, Halifax (Nova Scotia), 23-25 Aug 72.