Abstract: The invention resides in one embodiment in a multiple effect method of and apparatus for drying a solid material containing a vaporizable material which comprises establishing at least first and second fluidized beds containing the solid material in which in at least the first fluidized bed the fluidizing medium is the vaporizable material in vapor form and in which the fluidized beds are heated indirectly, such that vaporizable material is removed from the solid material, the vaporizable material removed from the solid material in the first fluidized bed being used to provide the indirect heating of the second fluidized bed.

Abstract: A feedback system for a multi-stage amplifier is disclosed which includes a nest of feedback loops centered on a particular stage, for example, on the output stage. This enables a very large amount of feedback to be applied to that stage, and enables constant return difference to be obtained for that stage over a nominated frequency range. Bode's limits for mid-band loop-gain magnitude and its rate of attenuation with frequency can be exceeded.

Abstract: In a process for the production of alumina which comprises the steps of digesting bauxite to produce a precipitate of alumina trihydrate containing uncombined moisture, drying the alumina trihydrate to reduce the uncombined moisture content thereof, and feeding the dried alumina trihydrate to a calciner to convert the alumina trihydrate to alumina, improved economy is achieved by drying the alumina trihydrate in a fluidized bed in which the fluidized mass is heated indirectly by means of steam which is available from the digestion and recovery system. Drying of the alumina trihydrate in this manner prior to feeding it to the calciner also reduces the fuel requirement in the calciner and enables the throughput of the calciner to be increased.

Abstract: A two-step process for the calcination of basic ferric sulphates in which the basic ferric sulphate is dehydrated by heating in a relatively low temperature range and the dehydrated product is then decomposed by heating in a relatively high temperature range.

Abstract: Apparatus for the continuous sulphur drossing of lead to reduce its copper content including a plurality of reaction vessels arranged in series, each reaction vessel having a curved bottom and a stirrer for creating a vortex of the contents. Bullion and sulphur are fed into the series through a vortex at controlled rates and through the series at controlled temperatures and a controlled total reaction time, optimally between 8 and 15 minutes. The bullion, dross and unreacted sulphur, if any, are overflowed from vessel to vessel and into an unagitated vessel for separation of the dross and bullion. The bullion feed device splits the undrossed bullion into a metered stream and an unmetered stream, the unmetered stream being utilized to carry away the separated dross for further processing.

Abstract: A continuous sulphur drossing process for the decoppering of lead comprising the steps of flowing lead bullion into the first of a series of at least two reaction vessels; continuously agitating the lead bullion in the first reaction vessel, adding sulphur to the lead bullion during the continuing agitation; continuously and concurrently transferring the lead bullion, dross arising from the copper reacted with the sulphur, and any unreacted sulphur from each reaction vessel to the next in the series without backmixing; agitating the contents of each reaction vessel; maintaining the total residence time of the materials in the reaction vessels below that in which a significatn amount of reversion to elemental copper would occur, thereby substantially preventing re-solution of copper in he bullion; continuously and concurrently transferring decoppered bullion and dross from the final reaction vessel in the series to an unagitated dross separation vessel; removing the dross from the surface of the decoppered bul

Abstract: This invention is for phosphinoline and phosphindoline compounds having the formula,Wherein n is 0 or 1; X is 0 or S; R.sup.3 is hydrogen or methyl; R.sup.5 is hydrogen or methyl, or may be bound to R.sup.13 to form a morpholino, piperidino or pyrrolidino ring; R.sup.7 is hydrogen or hydroxy; R.sup.11 and R.sup.12 are hydrogen; R.sup.13 is methyl, or R.sup.13 and R.sup.5 may be joined together as above stated to form a morpholino, piperidino, or pyrrolidino ring. The compounds are analgesics.