Abstract: An improved process for water demineralization involving the use of a first separate column of weakly acidic cation exchange resin, a second separate column of weakly basic anion exchange resin and a third separate column of weakly acidic cation exchange resin. The cation resin is buffered with an at least dihydroxy-substituted amine. When the saline feed is passed through the system, the cations of the feed are exchanged for the buffer, releasing buffered salts. The buffered salts when passed through the anion exchange column are split, releasing the buffer that is then deposited on the third cation resin column. The latter column is then used as the first separate column during the next demineralization cycle. Thus, the buffer is internally looped which prevents contamination of the product water and also resulting in a saving of buffer. This process allows the efficient use of weak cation and anion exchange resins in a separate, fixed-bed configuration.

Abstract: This patent describes a novel solid rocket propellant comprising a polyurethane binder, a solid ammonium perchlorate oxidizing agent, and an effective bond improving amount of a bonding agent having the general formula:X.sub.2 N(CH.sub.2 CH.sub.2 NX).sub.n CH.sub.2 CH.sub.2 NX.sub.2wherein n is an integer and can assume values from 1 to 12, and X is hydrogen, cyanoethyl, hydroxypropyl or mixtures thereof with the proviso that at least one of said X groups is hydrogen.

Abstract: An extendible nozzle for a rocket motor or the like which nozzle is positioned in the aft end of the motor is disclosed having a main nozzle portion with an exit and entrance thereto and a plurality of elongated petals representing longitudinal sections or strips of a conically shaped structure hingedly connected by means of hinges at their forward ends to the exit portion of the main nozzle portion. The petals are selectively movable from a first or stowed position where the petals are all radially outward and slightly forward of the hinge locations to a second or deployed position where the petals form a smooth conical extension of the exit portion of the main nozzle portion. The petals are positioned to be in as close proximity to the aft motor dome of the rocket motor as possible while still allowing the required envelope or spacing for rocket dome-mounted components which are necessary to accomplish other motor/nozzle functions.

Abstract: A device and method for manually everting a cloth or fabric tube where all manipulations may be visually monitored. The device comprises an elongated hollow body having a convergent passageway entrance at one end thereof and a fabric attachment member connected to a handle member adapted to be selectively introduced into or removed from the other end of said hollow body. The body portion of the tool is preferably cylindrical in configuration. The means connecting the handle member and the fabric attachment member is arranged within the interior of said hollow body when the handle member is introduced into said one end thereof. With the handle member so arranged, the fabric attachment means engages the open end of the cloth tube. The tube may then be everted by moving the handle outwardly from the hollow body, thereby pulling the end of the tube into the convergent passageway entrance. This causes the fabric tube to gather and move upwardly through the hollow body.

Abstract: Recovery of ion-exchange regenerants and precipitation of mineral salts is disclosed. The spent cation and anion regenerant streams are combined to form a weak dissociable complex of the regenerants and to reconstitute the removed inorganic mineral salt. The mixture is adjusted stoichiometrically to balance the anion and cation of the removed salt. The salt is precipitated by limiting solubility thereof either by concentrating the mixture or by reducing the solubility of the salts therein, suitably by the addition of a water-miscible solvent such as methanol. The complex is dissociated to reconstitute the separate anion and cation regenerants which are adjusted to the appropriate solvent concentration for recycle and reuse.

Abstract: An improved, closed-cycle process for regeneration of weakly acidic spent cation resins and for the recovery and recycle of the regenerants is disclosed. The improvement resides in the use of hydroxy or alkoxy substituted carboxylic acids as the cation resin regenerant. These acids and their metal salts are soluble and are high boiling and do not form azeotropes. When the spent cation regenerant is combined with the spent anion regenerant such as an amine salt, a weak, dissociable complex of the regenerants is formed and the metal salt is reconstituted. The complex is dissociated, preferably by distillation, into the separate regenerants which are recycled and the salt is recovered.

Abstract: The method and sensors are capable of measuring dynamic moduli of nongaseous fluid and semi-fluid materials. When cast in a castable-type material, such as solid rocket propellant, changes due to chemical aging of the propellant or other substances being tested may be detected. The sensors include a spacer separating a pair of piezoelectric crystals with substantially no air gaps between the crystals. One of the crystals is driven while the other is connected to a recording device. The measured response of the sensor in-situ or immersed in a work sample is compared with the response in air. The elastic modulus and loss tangent of the tested material may be computed based upon the amplitude and phase of the sensor's response.

Abstract: This patent describes a novel composition comprising the polymer of a butadiene polymer or other olefinic polymer containing functional groups and complementary reactive cross-linking agent such as polyisocyanate, aziridine or epoxide, and a stabilizer mixture therefor including (1) a secondary amine having the formula: ##EQU1## or wherein R is a monovalent aromatic group such as phenyl or naphthyl, and R' is a divalent aromatic group such as phenylene and (2) a thiodiester of the formula: ##EQU2## wherein R" is a monovalent alkyl or aryl group such as methyl, ethyl, pentyl, decyl, phenyl, naphthyl and the like and n is an integer from 1 to about 20.