Abstract: 1,1,1,2-Tetrafluoroethane is a good chain-transfer agent for the preparation of polymers of tetrafluoroethylene in aqueous colloidal dispersion.

Abstract: A housing block with a first passage and a second passage extending parallel to the first passage is attached to each membrane filter plate. A piston is mounted slidably in the first passage and a spacing bolt is positioned slidably in the second passage. A first circumferential groove which is connected with a compression compartment between elastic membranes extending radially exteriorly is introduced into the center of the first passage. The piston has a plurality of, advantageously four, axially extending piston grooves which connect with the circumferential groove in the open configuration and because of that the above mentioned compression compartment is connected with the surrounding atmosphere. The operation of the pistons is positively actuated by a counterweight and the sealing bolts are positioned in succession in a row. The motion of these spacing bolts is bounded by a stop piece.

Abstract: Fire extinguishant composition comprising a mixture of a finely divided aluminum compound and alkali metal, stannous or plumbous halide. Aluminum compound may be aluminum hydroxide, alumina or boehmite but preferably it is an alkali metal dawsonite. The metal halide may be an alkali metal, e.g. potassium iodide, bromide or chloride or stannous or plumbous iodide, bromide or chloride. Potassium iodide is preferred.

Abstract: New chromatographic materials have been developed to serve as the stationary phase of columns used in the separation of atmospheric gases. These materials consist of a crosslinked porous polymer matrix, e.g., a divinylbenzene polymer, into which has been embedded an inorganic complexed ion such as N,N'-ethylene-bis(acetylacetoniminato)-cobalt (II). Organic nitrogenous bases, such as pyridine, may be incorporated into the chelate polymer complexes to increase their chromatographic utility. With such materials, the process of gas chromatography is greatly simplified, especially in terms of time and quantity of material needed for a gas separation.

Abstract: A model for demonstrating a variety of crystal structures wherein vertical rods represent ionic or atomic coordinate axes and spheres movably mounted on the vertical rods represent ions or atoms is disclosed. A template covering some of the holes in a base defines a selected base hole pattern for establishing atomic coordinates. Spheres are of a selected size such that certain adjacent spheres are tangent to each other.