The use of exploding targets has become a popular practice aid in the military, law enforcement and consumer levels. The inventor has conceived and reduced to practice, in a preferred embodiment of the invention, a safe explosive target formulation that is initiated by low-velocity impact. This formulation represents a binary explosive in that the fuel and oxidizer are packaged separately until directly prior to use. Safe, explosive targets for high velocity applications are common. A formulation for low velocity projectile applications which employs an aluminum/magnesium alloy fuel and a potassium perchlorate/ammonium nitrate oxidizer is described.

A plug (1) for plugging wells, and in particular oil and gas wells, is provided. The plug (1) has a plug body formed from an outer metal tube (2) of a reduced thickness. The plug also has reinforcement means (4), attached to an inner surface of the outer tube (2), that give the plug a cross-sectional structural strength that is at least equivalent to that of a thicker metal tube. The plug has a central heater receiving void located along the axis of the plug to enable a plug deployment heater to be received therein. Also provided is a plug assembly (10) with a variable cross-sectional area in a plane perpendicular to the plane in which the assembly is deployed during the plugging of underground conduits.

A plug (1) for plugging wells, and in particular oil and gas wells, is provided. The plug (1) has a plug body formed from an outer metal tube (2) of a reduced thickness. The plug also has reinforcement means (4), attached to an inner surface of the outer tube (2), that give the plug a cross-sectional structural strength that is at least equivalent to that of a thicker metal tube. The plug has a central heater receiving void located along the axis of the plug to enable a plug deployment heater to be received therein. Also provided is a plug assembly (10) with a variable cross-sectional area in a plane perpendicular to the plane in which the assembly is deployed during the plugging of underground conduits.

A chemical reaction heat source for use in heaters used in down-hole applications is provided. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperatures down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

A chemical reaction heat source for use in heaters used in down-hole applications is provided. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperatures down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

A plug for plugging wells, and in particular oil and gas wells, is provided. The plug has a plug body formed from an outer metal tube of a reduced thickness. The plug also has reinforcement means, attached to an inner surface of the outer tube, that give the plug a cross-sectional structural strength that is at least equivalent to that of a thicker metal tube. The plug has a central heater receiving void located along the axis of the plug to enable a plug deployment heater to be received therein. Also provided is a plug assembly with a variable cross-sectional area in a plane perpendicular to the plane in which the assembly is deployed during the plugging of underground conduits.

A plug for plugging wells, and in particular oil and gas wells, is provided. The plug has a plug body formed from an outer metal tube of a reduced thickness. The plug also has reinforcement means, attached to an inner surface of the outer tube, that give the plug a cross-sectional structural strength that is at least equivalent to that of a thicker metal tube. The plug has a central heater receiving void located along the axis of the plug to enable a plug deployment heater to be received therein. Also provided is a plug assembly with a variable cross-sectional area in a plane perpendicular to the plane in which the assembly is deployed during the plugging of underground conduits.

A chain-reactive, heat-generating microcapsule comprises a first compartment including a first component and a second compartment including a second component. An isolating structure separates the first and second compartments. The isolating structure may rupture when heated above a normal ambient temperature and/or in response to a compressive force. The first component reacts with the second component to produce heat. The microcapsule may further incorporate a blowing agent that responds to heating. In some embodiments, a core within the first compartment comprises a blowing agent material that responds to the heat produced when the first and second components react. The microcapsules can be incorporated into a material comprising a heat-curable resin precursor such that heat generated by the microcapsules can be used to cure the resin precursor.

A rocket propellant includes a hydrocarbon blend having a total aromatic compounds content less than 0.5 mass percent, a specific energy of at least 18.4 KBtu/lb, and a mass density of at least 0.8150 grams per cubic centimeter. The propellant, which can be prepared by blending a refined kerosene with an isoparaffin and/or a cycloparaffin, exhibits a high volumetric heat of combustion and excellent thermal stability. This combination of properties is especially useful for fueling reusable launch vehicles employing regenerative cooling of engine components.

A chemical reaction heat source for use in heaters used in down-hole applications is provided. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperatures down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.