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A desimple-tailed study of the rate of interaction of citrate buffers with aniline to form anilides and imides shows that the basic mechanism follows essentially that previously described. Results show in particular that the rate of anhydride formation by the polycarboxylic acid is faster than from the previously studied succinic system and probably involves both the undissociated acid and its singly charged anion. The overall equilibria and rates for the total reaction were determined and the approach to equilibria checked with an analog computer. The speed and nature of the reaction suggest that these interactions may often be responsible for loss of activity of some drugs formulated with this buffer.

Summary: The mechanism of the adhesion of the suspension particles on the wall surface of the glass container is discussed. Two types of mechanism are found; 1) simple adhesion where no mutual affinity or interaction exists between the particle and the wall, 2) adhesion with affinity. In the case of the simple adhesion, the suspension particle is pressed against the wall and trapped by a thin medium film, whose pressure increases with decreasing of the medium film thickness. Important in this process is the liquid film formation on the wall. Under the pressure, the particle superdissolves into the thin liquid film at the contacting point, and the excess particle component produced deposits on both surfaces of the wall and the particle, where no direct pressure works upon. The adhesion strength increases as time goes by, since the deposition grows according to time, as long as the medium film presents and the pressure works on the particle. Adhesion due to deposition is not so popular as that due to affinity, but it is considered as an important basic form of the adhesion. For the affinity adhesion, the commonest affinity is a hydrophobic bonding effect, which may be explained byvan der Waals coefficient and by determination of sliding angle of the suspension particle in the dispersion medium. Electrostatic affinity is less popular than affinity by hydrophobic bonding, but adsorption of the medium component onto the particle or the wall sometimes causes the adhesion due to this. Zeta potential of chloramphenicol crystals and glass powder was measured and its influence on the adhesion was discussed in connection with adsorption of benzethonium chloride. It was found that the adhesion strength of this type does not increase with lapse of time.

Summary: The effect of several additives on the adhesion of the suspension particles to the wall of containers was studied for pharmaceutical suspension. For the combination of the chloramphenicol suspension and the glass wall, anionic surface active agents and some of high polymers were found to be agents for good preventing adhesion. Non-ionic and cationic surface active agents facilitated the adhesion, and gave an adhesion maximum point at a certain concentration in the aqueous media; the mechanism was elucidated by adsorption of the additive component upon the surface of the particle and the wall, and the hydrophobic bonding effect. Some pharmaceutical improvements for preventing the adhesion trouble were given.

Summary Particles of the pharmaceutical suspension often adhere on the container wall and cause several serious troubles. This adhesion proceeds by two steps; (1) particle trapping and (2) particle adhering. Particle trapping occurs only when the suspension spreads on the wall surface to make the even, thin liquid film of the medium, which traps the particles by pressure due to the surface tension of the medium acting upon the water line of the particle surface. The thinner film and the greater surface tension of the medium give the stronger trapping effect. The number of trapped particles is directly proportional to the concentration of the suspension and to square root of the particle diameter. The overall observed trappable nature of the particle was expressed by trappability constant.

Tartaric acid buffer has been shown to form a reactive intermediate in aqueous solution capable of rapidly acylating any nucleophilic compound present. With aniline as the nucleophile, the rate of formation of the intermediate, presumably an acid anhydride, has been found to proceed at roughly the same rate as that of succinic acid but slower than citric acid. Only the monoanilide was obtained in appreciable amount.

ALABAMAChanges in Health Personnel.—Dr. John I. Mitchell, Double Springs, health officer of Winston County for three years, has resigned effective October 1 to enter private practice either in Russellville or in Pell City, it was reported. —Dr. Frank M. Hall, Athens, has been named health officer of Alachua County, Gainesville, Fla.ARIZONAState Meeting to Be in Tucson.—The Arizona State Medical Association will hold its annual meeting at the Pioneer Hotel, Tucson, April 27-28, 1945. The scientific program will be presented by members of the staff of Baylor University College of Medicine, Houston, Texas.CALIFORNIASymposium on Psychotherapy.—The San Francisco Psychoanalytic Society held its semiannual meeting October 28-29 at the Ambassador Hotel, Los Angeles. One session was a symposium on short psychotherapy with Comdr. Uno H. Helgesson (MC) on "Experiences with Short Psychotherapy in Military Psychiatry"; Dr. Bernhard Berliner, San Francisco, "The Practice of Short