Abstract: A novel device and method are provided herein for the production of underwater sound. This device, termed a plasma jet underwater acoustic source includes a central electrode and a concentric insulator having a longitudinal bore to accommodate the central electrode, the bore being spaced from the central electrode by a longitudinally-extending annular chamber. A plasma cavity is bounded at its upper end by the central electrode, and is in communication with the annular chamber. The cavity is adapted to be connected to a gas supply, so that it may be filled with gas. An outer housing of electrically-conductive material surrounds the insulator and terminates in a centrally-apertured end plate whose central aperture provides an extension to the plasma cavity, the end plate being adapted to be grounded.

Abstract: A method of making a casting comprising the steps of, at a casting station, feeding molten metal from a primary source of molten metal into a mould cavity through an ingate below the top of the mould cavity, placing the cavity out of feeding relationship with the primary source by changing the orientation of the cavity relative to the direction of gravity to prevent flow of molten metal from the cavity towards the primary source and to permit of flow of metal from a secondary source to the cavity, the cavity being continuously connected to the primary source during said change of orientation, transferring the mould cavity to a cooling station spaced from the casting station and, at the cooling station, permitting molten metal to flow to the cavity from the secondary source while the metal in the cavity solidifies.

Abstract: It has unexpectedly been discovered that 1-(1-isocyanato-1-methylethyl)-3-(1-methylethenyl) benzene(m-TMI) can be emulsion copolymerized with other monomers into useful polymers. For example, it has been found that m-TMI can be emulsion copolymerized with diene monomers to produce polymers which contain pendant isocyanate groups. Such pendant isocyanate groups are useful in a variety of applications. For instance, such pendant isocyanate groups can be utilized as sites to which chemical agents, such as antidegradants, can be bound to the polymer. Elastomers which contain such pendant isocyanate groups are of value since they can be crosslinked without employing sulfur. Elastomers of this type which contain pendant isocyanate groups can also potentially be thermo-reversibly crosslinked.

Abstract: A frequency controlled oscillator arranged to be fabricated in integrated circuit form including a primary frequency controlled oscillator and a secondary frequency controlled oscillator with a counter arranged to periodically count pulses of the oscillation frequency of the secondary frequency controlled oscillator and to produce a first output signal if the count is less than a predetermined value and to produce a second output signal if the count is greater than a predetermined value, and control means providing a bias control signal in dependence on the output signals of the counter for tuning the oscillation frequency of both the secondary frequency controlled oscillator and the primary frequency controlled oscillator.

Abstract: A self-regulating heating article comprising a layer of material exhibiting a positive temperature coefficient of resistance (PTC) and said PTC layer having at least partially contiguous therewith at least one layer of constant wattage output material. The article operates such that when connected to an electric power source, the current flows through at least a portion of the thickness of the PTC layer and of the constant wattage layer.

Abstract: The aim of the invention is to measure the partial pressure of very small amounts of free hydrogen gas at various sites in the core of a nuclear reactor. A further aim is to construct such a device to be so rugged as to survive in the reactor environment. Another aim is to construct such a device of materials which will not significantly affect reactivity.

Abstract: The invention relates to a process for forming a cement composition which comprises mixing hydratable cement particles, water and an oil-in-water suspension wherein the oil droplets of the suspension are surrounded by colloidal particles having a zeta potential of between about +18 and -18 millivolts, and allowing the mixture to cure.

Abstract: This invention discloses a process for the polymerization of acrylamide and for the copolymerization of acrylamide with other monomers. It employs a ferrous/hydroperoxide redox initiator system that greatly enhances the molecular weight of the polymer formed. These high molecular weight acrylamide polymers offer outstanding advantages in enhanced oil recovery as injection water viscosifiers.

Abstract: A composition for use for the treatment of burns, cuts, wounds, abrasions and the like, comprises a pharmaceutically acceptable glycol, preferably propylene glycol, and a cellulose derivative, which is heat sterilizable, preferably hydroxyethyl cellulose. The composition optionally contains an antiseptic, an antibiotic and/or a topical corticosteroid.

Abstract: Disubstituted ethanes having a formula ##STR1## wherein R is alkyl, X is selected from hydrogen, ##STR2## wherein each R.sub.1 is selected from H, alkyl, alkoxy, halo and cyano and each of Q.sub.1, Q.sub.2, Q.sub.3 and Q.sub.4 is independently selected from H and F are useful as components of liquid crystal materials for electro-optical displays and compounds useful in the production of such components.

Abstract: Stable suspensions of oil and water are provided by surrounding the droplets of the suspended phase by colloidal particles to form an aggregate particle having a zeta potential between about +18 and -18 millivolts.A process for forming such stable suspensions of water and oil by adding to one of the liquid phases an anionic agent and a cationic agent to produce colloidal particles having a zeta potential between about +18 and -18 millivolts, then adding the other liquid phase to form the suspension.

Abstract: There are disclosed polymers which have nonionic surfactant moieties pendant to the polymeric backbone which exhibit activated sulfur vulcanization, a process for their preparation, and mixtures of polymeric cure activators and elastomers.

Abstract: Novel aqueous inorganic particle slurries, wherein some of the particles have had their charge potential altered to a sufficient extent to prevent segregation or settling of the particles, are described, along with a method for their preparation. The method of forming slurries of negatively charged particles comprises treating some of the particles with a cationic agent to reduce their charge and mixing these treated particles with the remainder of the particles to form a thick, cream-like flowable composition of a thixotropic nature. When slurries of positively charged particles are to be formed, an anionic agent is used instead of a cationic agent.

Abstract: A liquid crystal composition suitable for use as a two-frequency material in a two-frequency switching device comprises a mixture of:a first component comprising at least one diester compound having a formula: ##STR1## where R.sub.1 is an alkyl or alkoxy group, Z is an cycloalkyl or aryl ring structure and R.sub.2 is alkyl, alkoxy or halogen; or CN; and a second component comprising at least one compound having a formula: ##STR2## wherein R.sub.3 and R.sub.4 is each independently an alkyl or alkoxy group, ##STR3## is a trans-1,4-disubstituted cyclohexane or a benzene ring, Y is a cycloalkyl ring or a benzene ring optionally having a lateral halogen substituent and n is 0 or 1.

Abstract: A hydrogen measuring apparatus comprising two gamma thermometers. Both gamma thermometers are mounted adjacent and parallel to each other. Each is provided with a plurality of annular enclosed spaces formed in an elongated rod. Each annular space is provided with a hot junction of a difference thermocouple. The annular spaces of one of the gamma thermometers is either filled with a gas other than hydrogen, or surrounded by a hydrogen blocking material to prevent hydrogen contamination of the annular spaces. The annular spaces in the other gamma thermometer are placed in a vacuum and become contaminated with hydrogen. By comparing the power generation readings of the two thermometers free hydrogen partial pressure can be calculated.

Abstract: Composite inorganic articles are produced by bringing two separate inorganic slurries, each containing different ceramic materials, into contact with each other, simultaneously freezing the slurries while in contact with each other to form a unified frozen structure, thawing and drying the structure, and firing the unified structure.

Abstract: A self-regulating heating article comprising a layer of material exhibiting a positive temperature coefficient of resistance (PTC) and said PTC layer having at least partially contiguous therewith at least one layer of constant wattage output material. The article operates such that when connected to an electric power source, the current flows through at least a portion of the thickness of the PTC layer and of the constant wattage layer. In a preferred embodiment, upon heating the article, a change in dimensions as well as activation of an adhesive occurs.

Abstract: A composite useful as a ski sole comprising polyethylene particles in a polyethylene film, the former having a greater hardness or higher melt index than the latter, which is capable of renewably forming fibrils extending from a surface thereof under the abrasion characteristic of skiing conditions. The particles may have been treated with a material which is incompatible with or reduces the adhesion to the film-forming polyethylene.

Abstract: This invention discloses a novel class of polymeric diphenylamine compounds. The compounds are produced by reacting diphenylamine with a dialkylalkenylbenzene or dihydroxyalkylbenzene having either meta or para orientation in the presence of an acid catalyst.

Abstract: Novel conductive polymer compositions which exhibit useful PTC behavior are produced by cross-linking processes. By correlating the polymer, the conductive filler dispersed therein, and the cross-linking conditions, PTC compositions having desired resistance/temperature characteristics can be prepared. In particular the cross-linking can be carried out so as to provide compositions having a switching temperature around the cross-linking temperature. The invention is applicable to both elastomeric and thermoplastic polymers, and provides for the first time a method of making PTC compositions exhibiting useful PTC behavior from elastomers.