Propellant drying, continuous

After allowing to stand for a few minutes, the steam was turned into the jacket and agitation continued for 5—6 hours during which time most of the amyl acetate and some water were distilled off. The contents of the vessel were then run out and the grains of propellant dried and sieved(Ref 3) Refs l)Beil 2,131-2,(60-1) [143-4] 2)Marshall 1(1917),336 3)Bamett(19I9),82... 

The rolling operations that foUow take place first on hot (95°C) differential-speed roUs which dry and coUoid the paste and convert it iato sheet form, and then on even-speed roUs which produce smoothly surfaced propellant sheets ia which all iagredients have been uniformly iacorporated. The roU gap ia the differeatial roUs is adjustable to produce sheets of various thicknesses, and rolling is continued until the moisture is reduced to a predetermined level, usually less than 0.5%. The sheet is then cut off the roU. Differential rolling is potentially hazardous, and fires are not uncommon, although detonations are not apt to occur. Operations are conducted by remote control. 

Method 3(when acardite II centralites are present) a)Extract with chlf or methylene chloride ca lOg of finely divided propellant, evap the solvent and weigh the dried extract (wt 1 - centralite + acardite II) b)Treat the extracted material with aq AcOH at pH ca 4 and filter the mixt through cared sintered glass crucible. Rinse the residue, dry it to const wt and weigh(wt 2 = acardite II and wt 1 — wt 2 centralites) c)Continue. the analysis as described in procedures (c) to (g) of Method 4... 

The use of aerosol delivery systems continues to be a desirable means of administering locally acting agents to the lungs. Since the early 1990s there has been a surge of interest in the pulmonary delivery of proteins and peptides for systemic activity but to date none of these products have made it to market [1], During this period the major commercial successes have been in the form of dry powder systems [2] and alternative propellant systems [1], as will be discussed later in the chapter. The incidence of asthma and chronic obstructive disease continues to rise and the need for improvement and diversity of therapies remains a priority in their treatment [3]. 

Dry biend the Van Gei B and Rhodopoi 23 and add them to the water while mixing with a propeller stirrer at 1 BOO rpm. Continue mixing for 60 minutes. 

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