rosion problem. The case provides a prime example-representing no more than exercises in the study of electrochemical phenomena employing combinations of metals and environmental conditions chosen mainly to facilitate experiments for the convenience of the investigator and to enable him to make use of equipment and experimental techniques with which he is familiar or which are currently in vogue." (Corrosion, 33 (2), 76 (1977).)An important subject which was to have been presented is entitled, "What We Do Not Know about Corrosion". Unfortunately, the author, Dr. David A. Vermilyea was not able to participate. This message is recorded in two publications: Mater. Sci. Eng., 25, 29-34 (1976), and Phys. Today, 29, No. 9 (1976). Each is a powerful spring-board preface to launch a systematic future.A value-added feature, following the two-day lecture session, was a workshop conducted on the following day to provide answers to the question "What Can Be Done about It?"Here the authors of the 20 papers were invited to engage in dialogue with the audience. Five discussion leaders presided to introduce separate subject segments to stimulate discussion, as follows: K. Hamann, interfacial reactions; C. Kumins, transport through membranes; T. Fort, Jr., surface energetics; J. Patterson, corrosion inhibition; J. Garden, summary and future plans.

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Abstract:Chitosan was reacted with four concentrations (2.5, 5, 10 and 20 mmol) of glutamic acid resulting in four types of glutamic-chitosan hydrogels (GCs), the activity of the resulted compounds on the removal of copper(II) and nickel(II) from wastewater were tested. The results indicated that by increasing glutamic acid concentration from GCs-1 to GCs-4, the efficiency of removing Cu(II) and Ni(II) were decreased, which may be due to a decrease in the pore size of the hydrogels as a result of the increased degree of crosslinking.

The mechanical properties of solution-cast films of filled polymers are found to be very much enhanced when the polymer is strongly adsorbed on the filler in the casting solution. Acid-base interactions between polymer and filler promote such adsorption, subject to the acidic or basic nature of the solvent. ^-Potential measurements were used as a measure of acid-base interaction between filler and polymer in solvents of low dielectric constant. Thin films containing up to 60 vqI % filler were cast from both acidic and basic solvents. Relative values of Young's modulus and tensile strength were compared for each system using the equations of Kerner and Nielsen as a basis for the cases of good and poor adhesion. In a system with acidic polymer (post-chlorinated PVC) and basic filler (CaC03 or BaTi03) cast from an acidic solvent (CH2Cl2), both adhesion and mechanical properties were improved over the same system cast from a basic solvent (THF); adsorption measurements showed no polymer adsorption from THF, but rapid and strong adsorption from CH2CI2. For the most part, in systems where both polymer and filler were either acidic or basic, brittle films (or none at all) were obtained.

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