Langmuir-Adams trough

In most experiments, film pressures have been measured directly by means of a film balance or Langmuir-Adam trough. The principle of the method involves the direct measurement of the horizontal force on a float separating the film from... 

In the vibrating plate studies the liquid surface was formed in a waxed Langmuir-Adam trough in which the surface could be cleaned by waxed slides. Details of how cleanliness was controlled, how monolayers were spread, and how surface pressures were measured are described elsewhere (25). We studied numerous monolayers but only report sodium octadecyl sulfate and distearoyl lecithin monolayers. 

Measurements of the spreading pressure II at various values of the area A per molecule of a fihn of mjnistic acid C13H27.CO2H on M/lOO aqueous hydrochloric acid at 19 C have been made by means of a Langmuir-Adam trough by Allan and Alexander (Trans. Faraday Soc. 1954, 50, 863, supplemented by private communication from Allan). Some tjqiical results obtained in one nm are given in table 1. 

Fig. ni-14. Cross section of the PLAWM (Pockels-Langmuir-Adam-Wilson-McBain) trough. 

Landsteiner, blood groups 184 Langmuir trough 394 Langmuir-Adam film balance 394... 

The Langmuir-Adam surface balance (or trough) uses a technique... 

Surface Pressure and Surface Potential Measurements. The surface balance was Langmuir-Adam type with a glass trough as previously described (14), The sensitivity of the balance in terms of surface pressure was 0.1 dyne/cm. 

Figure 5.3 Film balances a. Langmuir trough having a movable barrier and a Wilhelmy tensiometer to measure the spreading pressure, n, for water insoluble monolayers, b. PLAWM (Pockels, Langmuir, Adam, Wilson and McBain) trough used for partially water-soluble monolayers, where a flexible membrane, which is fixed to the barrier, separates the surfactant solution and pure water departments to prevent the passage of dissolved surfactant molecules into the pure water department beneath the barrier.

Film Balance A shallow trough that is filled with a liquid on top of which is placed material that may form a monolayer. The surface area available can be adjusted by movable barriers, and any surface pressure thus created can be measured by means of a float. Also called Langmuir Film Balance, Langmuir Trough, and Pockels—Langmuir—Adam—Wilson—McBain Trough or PLAWM Trough. 

PLAWM Trough (Pockels—Langmuir—Adam—Wilson—McBain Trough)... 

Pockets—Langmuir—Adam—Wilson—McBain Trough See Film Balance. 

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