Vacuum microbalance, surface studies with

Surface Studies with the Vacuum Microbalance Instrumentation and Low-Temperature Applications T. N. Rhodin, Jr. 

Surface Studies with the Vacuum Microbalance High-Temperature Reactions Earl A. Gulbransen The Heterogeneous Oxidation of Carbon Monoxide Morris Katz... 

A chemical investigation of the surface oxides on diamond was undertaken by Boehm et al. (35). Using a fine particle size diamond powder with a specifie surface area of 17 m /gm, the oxidation was studied by use of a vacuum microbalance. Formation of surface oxides started at a measurable rate with pure oxygen at 260°. A weight loss due to formation of carbon oxides became apparent above 360°. 

All vacuum microbalances suitable for surface studies can best be described in terms of four different classes with operating and performance characteristics unique to each class. The advent of the simple precision microbalance seems to be with Warburg and Ihmori (6) in 1886. From then on numerous designs have been described. Excellent reviews cover the steady progress in precision microgravimetry from those of Pettersson (7) (Sweden, 1915), through Emich (8) (Germany,... 

The results of studies of copper surfaces by low-temperature adsorption isotherms may be summarized as follows. True surface areas of metallic specimens as small as 10 sq. cm. can be derived with a precision of 6% from low-temperature adsorption isotherms using vacuum microbalance techniques. This method is of special value in determining the average thickness of corrosion films formed by the reaction of gases or liquids with solids. The effect of progressive oxidation of a rough polycrystalline metal surface is to decrease the surface area to a point where the roughness factor approaches unity. 

The adsorption isotherms are measured with a quartz beam vacuum microbalance of high sensitivity. The surfaces studied are... 

---