Abstract: The present invention relates to the field of the continuous manufacture of composite pyrotechnic products.A heat-curable liquid binder (3) is mixed with a thickening filler (4) in a mixer (1) so as to obtain a viscous premix (2) which is unreactive at ambient temperature and which can be subsequently mixed with oxidizing fillers (17) to give, after extrusion and chopping, intermediate products (24) which are not yet crosslinked but which have stable geometrical dimensions. The structure of the products (24) is subsequently set by crosslinking the binder in an oven (26).The invention permits the continuous industrial manufacture in series of small crosslinked composite pyrotechnic charges without any "pot life" constraint since the binder does not change at ambient temperature.

Abstract: A method for lining a blast furnace or other metallurgical vessel in stages uses a plurality of porous consumable forms and a pumpable casting composition. A form member, including a rigid support frame and a porous consumable form mounted thereto, is installed in a lower portion of the vessel being lined, and is spaced from the vessel wall. Casting composition is then pumped into the space between the consumable form and the vessel wall, and is permitted to harden. Then, another form member is positioned above the first, and casting composition is pumped into the space between the second form member and the vessel wall. This process is repeated, using stacked form members, until the refractory lining is completely installed.

Abstract: Gas generant compositions without highly toxic azides are provided which, upon combustion, are converted into gaseous products with only small amounts of solid combustion products thereby minimizing the gas filtration problem. Gas generants having ammonium nitrate safely phase stabilized by mixture with wet triaminoguanidine are provided. A process for safely preparing the gas generants is also provided. These compositions are especially suitable for inflating automotive and aircraft occupant restraint bags.

Abstract: The present invention relates to a concrete forming system and method permitting a series of stacked concrete slabs to be formed at a work site. The system includes a vertical support member configured to the work surface, concrete form members for defining a desired shape for a concrete slab and horizontal adjustment members for attachment of the form members to the vertical support member. Through use of the system, a series of stacked concrete slabs can be successively poured one on top of the other.

Abstract: The present invention provides a multi-component explosive composition coising 2-ethylhexyl nitrate and a granular solid oxidizer. An optional additional component is a second fuel, e.g., aluminum. An optional component in the absence of the second fuel is azodicarbonamide. Methods for making the explosive are provided.

Abstract: In a method of construction of a reinforced concrete diaphragm floor of a nuclear reactor reinforced concrete containment vessel, a bottom surface of the diaphragm floor is provided in the form of an iron plate. The iron plate, an iron bar beam portion for supporting the load provided by concrete during a concrete pouring time, and a reinforcing bar member to be buried in the concrete of the diaphragm floor are assembled outside of a building in which the nuclear reactor is to be embodied. The above members are carried using lifting machinery and are set in a permanent receiving member which is provided on both a main body of the nuclear reactor pressure vessel and a steel member serving as a concrete mold frame of an outer wall of the nuclear reactor reinforced concrete vessel. A concrete pouring is carried out in stages so as to form successive layers of concrete during plural pouring times.

Abstract: A process for producing ultra-fine particles of calcia-stabilized zirconia in which a precursor mixture (which contains from about 80 to about 96 mole percent of zirconium ion, from about 20 to about 4 mole percent of calcium ion, a nitrogen-containing fuel, and a solvent) is dried and then subjected to a temperature of from about 275 to about 750 degrees centigrade and an atmosphere with a relative humidity of less than about 60 percent, thereby causing the dried particles to react in a vigorous manner and to form a combusted powder.

Abstract: A high energy shock-insensitive explosive composition for use in deformable warheads. This high energy shock-insensitive explosive composition is comprised of a shock-insensitive explosive and hexa-nitro-hexa-aza-isowurtzitane constituting about 35-45 wt. % and a having an average particle size of about 3 .mu.m. The high performance explosive consists of ammonium nitrate, nitroguanidine, 3-nitro-1,2, 4-triazol-5-one, or mixtures of the three and constitutes about 30-40 wt. %.The CL-20 explosive is wet ground in aqueous alcohol to reduce the size thereof, prior to incorporation in the explosive.

Abstract: A roller compacted concrete industrial floor slab is formed by surface finishing the slab by using a separate thin topping bonded to a roughened surface of the RCC, or by manipulating the RCC surface itself by working into its surface a finish mixture of cement-coated, rice-sized grit in a moisture saturated condition to fill any voids in the surface.

Abstract: High-flexural-strength concrete is produced by mixing wet hydraulic cement-sand mixture with coarse, flat, tabular aggregate, pouring the resulting mixture into a form in a shallow layer, vibrating the form containing the mixture, thereby orienting the coarse aggregate particles, pouring another shallow layer of the mixture into the form, again vibrating the form, and repeating these processes until the form has been filled to the desired level. The mixture then is allowed to cure. Cast-in-place items are prepared by placing thin layers or lifts of oriented, tabular-aggregate concrete into conventional forms and vibrating each lift using flat-plate vibrators.

Abstract: In the production of spherulitic nitroguanidine having a high bulk and tap ensity nitroguanidine is dissolved in dipolar, aprotic solvents, e.g. DMF, DMSO, NMP, etc., by heating to above the saturation temperature t.sub.s and the supersaturated solution is cooled with a controlled temperature gradient (.degree.C./min), crystallization being assisted by the addition of particulate, spherulitic material. In order to obtain spherical nitroguanidine with high yield in a continuous process and with mother liquor reuse, during the heating to above the saturation temperature t.sub.s, spherical control particles with a diameter of 5 to 500 .mu.m are regularly added to the solution in a quantity of 0.05 to 5.00 mass %. The particle size is chosen in such a way that, as a function of the solution behaviour of the nitroguanidine used and its concentration, on dropping below the saturation temperature spherical control particles are still present in the indicated quantity in the supersaturated solution.

Abstract: A method and an apparatus for reducing the grain size of crystalline explosive provide for, first of all, dissolving the coarse crystalline explosive in an organic solvent. Subsequently, the dissolved explosive is brought together with ice water in a precipitation reactor. In the precipitation reactor the precipitation and crystallization of the explosive occur, while turbulent agitation takes place. A filtration stage is connected downstream of the precipitation reactor. A fine crystalline explosive is obtained, having a mean particle size of from 4 to 6 micrometers.

Abstract: The present invention is directed to improved tank or containment vessels and processes and apparatus for their construction. The tanks or containment vessels usually consist of circular walls resting on a base and a dome supported by the walls. The dome of the subject prestressed tank is formed by deploying or creating a membrane on the base, applying one or more layers of rigidifying material (and prestressing or reinforcing material if needed) on the membrane and then forming said membrane into a dome before the rigidifying material sets by the selective introduction of compressed air at appropriate locations between the base and the membrane. The hardening of the rigidifying material results in a composite preformed rigid roof or dome having a membrane liner and an overlay of composite construction. Once the walls are created, air pressure can be further utilized to raise this preformed composite dome upward to a predetermined height after which it is fastened to the walls.

Abstract: A continuous process of manufacturing black powder and black powder substitute using a twin screw extruder is disclosed. Guar gum mixed with the composition at a concentration in the range from 0.05% to 0.5%, by weight, dramatically reduced the friction in the dies and permitted extrusion of the powder at much lower water levels. Different size dies used in combination with face cutting of the extruded strands produce various sized granules. The process can be operated remotely and automatically. The process reduces the number of buildings, equipment and personnel required to manufacture black powder or black powder substitute. The process produces more uniform and reproducible particle sizes.

Abstract: Modular Structures preferably usable to form human habitations in outer space are fabricated by molding. A mold comprising progressively surrounding flexible walls defines progressively surrounding cavities. A selected cavity or cavities are inflated or pressurized, as with gas, to distend to assume a predetermined configuration. Another selected cavity or cavities are injected with mold material, which is then allowed to harden. A pressurized cavity or cavities may be evacuated and then filled with mold material. In this manner, a strong structure is progressively formed is subsequent injection and hardening steps. In alternative embodiments of the molding method, supports or reinforcing members are placed within cavities prior to inflation and material injection. These supports space apart adjacent flexible mold walls and force the flexible walls to assume a desired configuration under inflated conditions.

Abstract: A process for producing ultra-fine yttrium-iron-garnet particles. In the first step of this process, a ceramic precursor material containing yettrium and ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A process for producing ultra-fine barium hexaferrite particles. In the first step of this process, a ceramic precursor material containing barium and trivalent ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A process for producing a sintered body from untra-fine superconductive particles. In the first step of this process, a ceramic precursor material containing yttrium, barium and copper cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided; the nitrogen-containing material contains at least three nitrogen atoms, at least one oxygen atom, and at least one carbon atom. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A method for placing concrete on a rock foundation to construct a massive concrete structure, such as a dam, a bridge pier or a foundation of a building, precludes development of cracks in the concrete by thermal stress.

Abstract: A roller compacted concrete industrial floor slab is formed by surface finishing the slab by using a separate thin topping bonded to a roughened surface of the RCC, or by manipulating the RCC surface itself by working into its surface a finish mixture of cement-coated, rice-sized grit in a moisture saturated condition to fill any voids in the surface.

Abstract: Reduction of the grain size of crystalline explosive.A method and an apparatus for reducing the grain size of crystalline explosive provide for, first of all, dissolving the coarse crystalline explosive in an organic solvent. Subsequently, the dissolved explosive is brought together with ice water in a precipitation reactor. In the precipitation reactor the precipitation and crystallization of the explosive occur, while turbulent agitation takes place. A filtration stage is connected downstream of the precipitation reactor. A fine crystalline explosive is obtained, having a mean particle size of from 4 to 6 micrometers.

Abstract: A method for forming an elongated concrete structure (20) which extends in a first direction and includes at least one outer surface (26) with a textured pattern having concave and convex portions which extend other than in just the first direction. The system comprises one or two elongated planar forms (32 or 32a/32b) having a reverse image of a textured pattern on one side (202) thereof, a conventional slip former (30), and a side arm assembly (150) coupled to the slip former for supporting the one form(s). The form(s) is erected prior to formation of the structure, remains standing during formation of the structure, and is disassembled a predetermined period of time after the concrete structure has been formed. The side arm assembly (150) slidingly engages the outer surface of the form(s) as the slip former (30) is moved in the first direction.

Abstract: The present invention is directed to a method for preparing or repairing a machine foundation by using a hollow form which surrounds vertically extending reinforcement rods and is filled with a fortifying material to secure the hollow form to a slab. The form is preferably made of an aggregate filled thermosetting resin or a thermoplastic resin which are corrosion and chemical resistant materials free from fluid attack such as the liquids in the machine, for example, in a pump the fluids being either the lubricating fluids or the fluids being pumped. More particularly, the present invention is directed to a hollow form which may be used either to prepare a machine foundation or to repair a degraded slab or foundation and preferably is a single form.

Abstract: This invention relates to improved polyurea coating compositions for particluate solids, and especially for fillers which are useful in solid rocket propellants. The composition is a copolymer of a primary or secondary amine and 3-nitrazapentane diisocyanate.

Abstract: A pyrotechnic mixture in the form of granulates, encompassing a nitrogen-generating substance, an inorganic oxidizing medium and a binder constituted of silicone rubber. Also disclosed is a process for the production of this pyrotechnic mixture, as well as a gas generator for an airbag which contains the pyrotechnic mixture as a propellent charge. The pyrotechnic mixture is in the form of granulates for a propellent charge which generates a non-toxic gas, encompassing the nitrogen-generating substance, especially an alkali metal azide or earth alkali metal azide, an inorganic oxidizing medium consisting of alkali metal nitrate and/or alkaline earth metal nitrate and silicone rubber.

Abstract: A pyrotechnic mixture in the form of granulates, encompassing a nitrogen-generating substance, an inorganic oxidizing medium and a binder constituted of silicone rubber. Also disclosed is a process for the production of this pyrotechnic mixture, as well as a gas generator for an airbag which contains the pyrotechnic mixture as a propellent charge. The pyrotechnic mixture is in the form of granulates for a propellent charge which generates a non-toxic gas, encompassing the nitrogen-generating substance, especially an alkali metal azide or earth alkali metal azide, an inorganic oxidizing medium consisting of alkali metal nitrate and/or alkaline earth metal nitrate and silicone rubber.

Abstract: In gas generant compositions utilizing as fuel, at least in part, tartaric acid, aqueous processing is improved through the use of d,1-tartaric acid over naturally-occurring 1-tartaric acid.

Abstract: There is provided a process for manufacturing a granular igniter, which facilitates control of the igniter preparation, handling of the granule igniter and improvement in manufacturized yield. The present invention also provides a process for manufacturing a granular igniter which is free from toxic gas generation when burned and which has excellent fluidity. The present invention moreover reduces the number of manufacturing process facilitating the production process, and reducing production costs.An igniter containing boron and potassium nitrate are mixed together with water in a homogenizer to form a homogeneous slurry. The mixing ratio of the igniter to the water is set in the range of 1.0:0.6 to 1.0:1.6 in terms of weight ratio. The slurry is sprayed in a spray dryer where it is dried and granulated. Micropowder, which failed to be collected as the granule, is recovered through a cyclone, and recirculated as the raw material.

Abstract: A compactable composite explosive consisting of 90 weight % to 95 weight % of a raw explosive material being RDX, 5 weight % to 10 weight % of ethylene vinyl acetate copolymer resin containing vinyl acetate in a content of 10 % to 20 % and 0 weight % to 0.5 weight % of dioctyl adipate (D.O.A.) or graphite. This composite explosive is usable as a main charge or a booster of a highly precise arms system. The invention also provides a method for producing a compactable composite explosive, which comprises the steps of dissolving a binder of ethylene vinyl acetate copolymer resin in a solvent of toluene to prepare a solution, injecting the solution into RDX dispersed in a water, forming a granular product from the obtained mixture, distilling primarily the product, *adding toluene into the product, and distilling secondarily the product. The amount of added toluene is 1.0 time to 3.0 times the amount of the binder measured after the primary distillation.

Abstract: A method of making gas generation compositions is provided comprising the steps of dry mixing an oxidizing agent, an organic acid, an iron compound and carbon to form a dry mixed product composition, without cooking, and then introducing a binder, such as water, to the composition, compacting the bound composition, comminuting the compacted bound composition to form granules and drying the compacted granules without cooking.

Abstract: A method of forming a continuous structure includes the steps of flowing a first liquid reactive resin forming material over a base surface, forming a first thin substantially uniform layer thereof and gelling the first layer. A second liquid resin forming material is flowed through an orifice under pressure forming a liquid stream thereof. The liquid stream is gelled to form a continuous filament with structural integrity as it advances toward the first gelled layer. The filament is contacted with the first layer and distributed thereover in a preselected pattern forming a porous non-woven filament blanket. A particulate solid material is distributed substantially uniformly over the filament blanket. A third liquid resin forming material is flowed over the blanket forming a second thin substantially uniform layer of the third liquid resin forming material and the layer is gelled.

Abstract: Gas generant compositions without highly toxic azides are provided which, upon combustion, are converted into gaseous products with only small amounts of solid combustion products thereby minimizing the gas filtration problem. A process for safely preparing gas generants which utilize the nitrogen containing fuel TAGN in the composition are provided. These compositions are especially suitable for inflating automotive and aircraft occupant restraint bags. The present invention advantageously and safely combines TAGN with phase stabilized ammonium nitrate (PSAN) to achieve production of a high volume of non-toxic gas with only small amounts of solid combustion products.

Abstract: The specification discloses a method for making a high density prill particularly useful in making an emulsion explosive composition. The method comprises incorporating certain sulfonate additives during the prilling process in order to make a porous ammonium nitrate matrix having a density of at least about 54 pounds per cubic foot (0.86 kg/L) and a concentration of greater than about 99.5 wt. % ammonium nitrate which exhibits a high oil absorption capacity.

Abstract: A method of constructing modular wall and floor units, and modular manufactured buildings from such units, is disclosed. The use of a metal-compatible cementitious building material and a unique technique for panel formation allows for the simple and simultaneous formation of wall or floor panels and integration of those panels with the reinforcing and supporting frames to form "half sections" of modular building walls and floors. These half sections can then be readily provided with in-wall and through-wall services at the factory in a manner which permits the workers to have clear access to the appropriate sections of the building for easy installation of such services. Upon completion of the installation of services, the corresponding half sections can be joined to form fully integrated and framed units and buildings including walls, floors or ceilings with a minimum of effort.

Abstract: There is disclosed a propellent having a deterred burn rate. The propellent is a particulate containing a nitrocellulose base and a cellulosic thermoplastic deterrent, preferably cellulose acetate butyrate or cellulose acetate propionate. The deterrent is gradationally dispersed within the particulate with the greatest concentration of deterrent at the particulate periphery.

Abstract: A process for manufacturing a flue made of fiber-reinforced plastic (FRP), particularly of a stack for discharging chemically aggressive fumes, consists of manufacturing the FRP flue directly inside the stack. The apparatus for performing this process includes a rotating carousel which supports a first work station, a second work station and at least a third work station to progressively and constantly deposit on a stationary mold at least one first layer of chemically-resistant material and at least one layer of mechanically-resistant material in order to form, without discontinuities, a central portion of the flue of the stack.

Abstract: An apparatus is used to support and move vertically an erected form assembly during the construction of a building with a plurality of stories. The stories include a lower story and an upper story. Each of the lower and upper stories is formed previously with a concrete wall structure that has surrounding walls formed integrally with reinforced horizontal beams which confine an interior space. The apparatus includes a form support body that can extend across the interior space of the upper story and that has a top side on which the erected form assembly can rest. A plurality of legs extend downwardly from the form support body. Each leg has a lower portion associated with a clamping unit in order to fix releasably the leg to one of the reinforced horizontal beams of the lower story. A horizontal support bar is located below and is spaced from the form support body.

Abstract: A process for forming a grain (10) of gas generating material includes the step of forming pieces (86) of gas generating material, and further includes the step of forming the grain (10) as a compacted agglomeration of the pieces (86) of gas generating material. The pieces (86) of gas generating material are formed by pressing a particle mixture (60) under a first pressure. The grain (10) is formed by pressing the pieces (86) together under a second pressure which is less than the first pressure.

Abstract: The present invention is directed to a mold for forming concrete walkways or surfaces. The mold incorporates a plurality of openings for receiving concrete therein. The mold forms a single concrete slab having a simulated brick or rock pattern on it's surface. Concrete walkways are formed by placing the mold of the invention on a surface and pouring concrete in the openings. Upon removal of the mold, the concrete retains the pattern. The procedure is repeated to form a walkway of a desired length, width and configuration.

Abstract: An apparatus for homogenizing plastic explosive material comprises a frame aving a base and spaced first and second supports extending perpendicularly therefrom in parallel. First and second spaced parallel generally cylindrical rolls are provided. Each roll is journaled at opposite end portions thereof to the supports. Each roll has an uninterrupted peripheral surface portion for engagement with the plastic explosive material. A crank is operably associated with one of the rolls at a first end thereof for rotating the roll. Gears meshingly interconnect the rolls at a second end thereof so that rotation of the one roll causes associated rotation of the other roll. Plastics explosive material is caused to be drawn between the rolls by their rotation so as to be homogenized.

Abstract: A present method involves preparing an anhydrous gas generant by forming a quantity of granulated anhydrous gas generating material into a shaped charge wherein the gas generating material is an oxidizer and at least one fuel selected from the group consisting of tetrazoles. More particularly, a preferred method involves preparing an anhydrous gas generating composition by preparing a slurry of gas generating material which comprises oxidizer particles larger than 1 micron and fuel particles larger than 1 micron wherein the oxidizer is selected from the group consisting of a metal peroxide, an inorganic nitrate, an inorganic nitrite, a metal oxide, a metal hydroxide, an inorganic chlorate, an inorganic perchlorate, or a mixture thereof, and the fuel is selected from the group consisting of tetrazoles; granulating the slurry to obtain granules of a selected weight average particle size; drying the granules to an anhydrous condition; and pelletizing the anhydrous granules.

Abstract: A process for producing ultra-fine ceramic particles in which droplets are formed from a ceramic precursor mixture containing a metal cation, a nitrogen-containing fuel, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen containing fuel. The nitrogen-containing fuel contains at least three nitrogen atoms, at least one oxygen atom, and at least one carbon atom. The ceramic precursor mixture is dried to remove at least 85 weight percent of the solvent, and the dried mixture is then ignited to form a combusted powder.

Abstract: A process forms decoy flare pellets which satisfy predetermined burn requirements without milling additional grooves into the pellet flare material after that material is consolidated. The process includes providing sufficient surface area to the flare material during consolidation to eliminate the need for milling. Consolidated flare pellets are then coated with an ignition composition and installed in a decoy flare housing.

Abstract: The method of making the casing comprises the steps of preparing a powder mixture consisting predominantly of a metal powder mixed with a minor proportion of graphite powder ranging from about 0.2% to about 2%, preferably 0.8% by weight, while the metal powder ranges from about 99.8% to about 98% by weight. The powder material is compressed into a casing mold to a molded density ranging from about 0.21 to about 0.24, preferably 0.23 of a pound per cubic inch. The molded powder is sintered in an inert atmosphere at a temperature ranging from about 1500 to about 1700, preferably 1600.degree. F. for a time sufficient to unite the molded powder into a brittle porous frangible casing. The graphite powder vaporizes and escapes from the molded casing during the sintering step whereby porosity and frangibility are imparted to the casing.

Abstract: A method of fabricating a concrete floor having an autogenous hard high gloss finish that does not require further coatings includes pouring a designed concrete mix to establish a slab having an upper surface slightly below the level determined for the finished floor. A finishing floor surface layer is created by applying an amount of a dry shake dressing material containing quartz crystals and a coloring agent, but no coarse aggregate, to the upper surface of the slab and floating the surface until the finishing layer reaches predetermined amount which cures to form a generally monolithic structure with the slab but having a higher compressive strength when fully cured. Necessary expansion joints are provided. The floor is coated with a curing sealer and allowed to cure for approximately 30 days, or until it reaches a predetermined compressive strength. The sealer material is removed and the expansion joints are sealed.

Abstract: Slurry and spray dried azide-based gas generant intermediates are made having a hydrazoic acid content of less than about 3.times.10 EXP(-3) M/L, a pH of greater than 8.0 up to about 12.5, and impurity metal ions Ca, Mg, Pb, Fe, Mn and Cu, each below about 25 ppm. These intermediates are made by slurrying powdered ingredients of the azide and oxidizer/reactant in water, wet grinding the slurry and spray drying to form a particulate material which is molded into pellets or tablets which are useful as the gas generant in vehicle crash bags or inflators. The basicity of the water is adjusted to a pH of greater than 8.0 up to about 12.5, preferably about 10, by the addition of a base, such as NaOH, followed by the addition of such solid ingredients as S, MoS.sub.2 and NaN.sub.3, and preferably the NaN.sub.3 is added last, whereby hydrazoic acid production is minimized. The contaminant Ca and Mg ions are minimized by softening the water supplied.

Abstract: Graphite fibers (62) are mixed with other materials (22) to form gas generating material (10) for use in an air bag inflator. The graphite fibers are first chopped to a desired short length by forming a mixture of fluid and relatively long graphite fibers in a container (50) having therein a rotatable blade (58), and rotating the blade continuously for a period of time to chop the graphite fibers to a shorter and more uniform length. The viscosity of the mixture in the container is increased as the blade rotates in the container, preferably through evaporation or boiling which counteracts the viscosity decreasing effect of fiber shortening.

Abstract: An improved dome structure on a base is disclosed comprising, in the preferred embodiment, of a membrane sandwiched between layers of rigidifying material such as shotcrete or reinforced composite which also serve to embed radial wires and circumferential tensioned prestressing. Various types of circumferential tensioned prestressing can be applied to minimize bursting stresses and can consist of steel wire as well as fiber or steel-reinforced tape. Further layers of rigidifying material can then be applied over the circumferential prestressing as a final protection and cover. The radial wires can contain spacers or hooks to preclude the circumferential prestressing from riding up on the structure. The lower portion of the dome can include a reverse curvature to minimize stresses and stabilize the structure. The rigidifying material may be composite which can be hardened by light curing. A second outer membrane can also be used for weather protection.

Abstract: A process for manufacturing a gas generating material includes preparing a hot solution of a metal azide, preferably sodium azide, with metal oxide particles, preferably iron oxide particles, suspended in the solution. The metal azide is precipitated from the solution. The step of precipitating the metal azide from the solution includes cooling the hot solution to decrease the solubility of the metal azide in the solute. The metal azide precipitate and the iron oxide particles are then separated from the liquid.

Abstract: A process for the production of explosives grade ammonium nitrate prill (EGAN) comprises the steps of(A). producing seed ammonium nitrate prill as substantially monosized prills; and then(B). fattening using melt/solution of ammonium or mixed nitrates, with drying and thermal treatments, the seed prill in an inclined rotating jacketed pan granulator or a cascade of such pans to produce a final fattened EGAN prill product preferably having at most about 4 mm diameter.