Abstract: A tunnel-forming overcast structure for incorporation in the installation of an overcast construction at the intersection of two intersecting passages in a mine, each passage constituting an airway for flow of air for mine ventilation having an upstream and a downstream mouth at the intersection. The structure includes a pair of generally parallel side walls each having a top and a deck extending from the top of one of the side walls to the top of the other side wall and connected to the side walls. Each side wall comprises a plurality of elongate generally vertically extensible panels extending generally vertically in side-by-side relation. Each panel includes an upper member and a lower member, one of the members having a sliding fit in the other. The lower members are in a relatively non-extensible position with respect to the upper members in the structure and are ultimately extensible for completing walling off of the upstream and downstream mouths of one of the airways.

Abstract: An overcast system for a mine is disclosed. The system includes and overcast positioned at an intersection of mine passageways and operable to direct airflow through the passageways in a desired flow pattern at the intersection. Stairways are positioned adjacent opposite sides of the overcast providing a means for people to traverse between the opposite sides of the overcast. The stairways are self adjusting to accommodate overcasts of different heights while providing generally horizontal steps. The stairways are constructed with knockdown assembly means to provide for easy assembly and disassembly in the mine.

Abstract: A permanent mine stopping comprising two spaced-apart metal walls with a filling in the space therebetween keyed or adhesively bonded to the walls and having sufficient strength in tension to constitute the walls and the filling as a permanently integrated composite structure in which the walls act as flanges in conjunction with the filling as a web. Also, a method of constructing the stopping using extensible panels to construct the walls, and an extensible panel for use in constructing a stopping with the keying.

Abstract: A mine stopping comprising a wall extending across a passageway in a mine to close the passageway. The wall has an opening therein. A door is hinged adjacent the opening for swinging between a closed position in which the door closes the opening to inhibit the passage of air therethrough, a first open position in which the door is moved in one direction away from the closed position, and a second open position in which the door is swung in an opposite direction away from the closed position. The door is movable to either of the first and second open positions when the door is subjected to substantial concussive air pressure thereby to permit concussive air to pass through the opening in both directions.

Abstract: A skin blister method and apparatus are disclosed to evaluate and quantify epidermal nerves by separating an epidermis sample. The method is useful for a variety of purposes including diagnosis of neuropathy or nerve injury from any cause; measurement of the time course and character of nerve regeneration with and without modifying influences; and measurement of the response of normal, abnormal or regenerating nerves to exposure to various types of chemical or physical modalities. The principle step in the process of the invention is the creation of a skin blister, preferably by means of negative pressure. The blister consists of the epidermis, its nerves and fluid. The epidermis is subsequently studied by one or more of a variety of processes. The apparatus of the invention comprises a capsule with a chamber which is connected to a gage, pump and connecting valves.

Abstract: A door system for closing a doorway in a mine stopping includes a door hinged adjacent the doorway for swinging relative to the stopping between a closed position and an open position. A keeper is mounted in fixed position relative to the doorway. A latch mechanism is cooperable with the keeper for latching the door in its closed position. The latch mechanism has a detent portion and is operable to move the detent portion between a latching position in which the detent portion engages the keeper for latching the door closed, and an unlatching position in which the detent portion is disengaged from the keeper for allowing the door to be opened.

Abstract: A system for controlling a first device having a first input for controlling operation of the first device and having a first output indicating status of the first device, and a second device operating in conjunction with the first device and having a second input for controlling operation of the second device and having a second output indicating status of the second device. The system includes first and second serial sequencers. The first serial sequencer controls the first device, wherein the first output of the first device is a first shared output. The first sequencer has an input connected to the first shared output of the first device for monitoring the status of the first device, and has an output connected to the first input of the first device for controlling operation of the first device.

Abstract: A method for reducing the sulfur content in combustion gases from burning coal includes the steps of applying opposite electrostic charges to fuel particles and to reaction particles, and mixing the oppositely charged particles prior to combustion to facilitate the formation of sulfur compounds from sulfur in the fuel upon combustion of the fuel, to thereby reduce the sulfur content in the combustion gases. The reaction particles are preferably a carbonate such as CaCO.sub.3 and MgCO.sub.3. The apparatus for implementing the method includes a first pneumatic line for conveying fuel particles, and a first electrostatic charging device for applying an electrostatic charge to the fuel particles conveyed in the line; and a second pneumatic line for conveying carbonate particles, and a second electrostatic charging device for applying an electrostatic charge to the carbonate particles conveyed in the line that is opposite in polarity to the charge applied to the fuel particles.

Abstract: A mine ventilation structure for installation at the intersection of first and second passageways in a mine. The ventilation structure defines a first passage communicating with the first passageway and a second passage communicating with the second passageway. The ventilation structure includes a pair of generally parallel, spaced-apart side walls defining the side walls of the first passage, and a plurality of elongate deck panels extending between the side walls and forming the roof of one of the first and second passages and the floor of the other of the first and second passages. Each deck panel is a sheet metal panel generally of inverted channel shape in transverse cross section, having an upper web and side flanges extending down from the upper web at opposite sides of the web. Tie bars hold the deck panels together in fixed side-by-side relation with the side flanges of the panels closely adjacent one another so that the webs of the panels form a substantially continuous surface.

Abstract: A structure including at least two generally parallel, spaced-apart side walls, and a plurality of roof panels extending between the side walls for forming the roof of the structure. Each roof panel has opposite ends overlying the upper ends of respective side walls. The roof panels and side wails are constructed with a bayonet connection device for quick connection.

Abstract: A power mine door system including a door frame to be installed in a mine passageway to define a generally rectangular doorway. A mine door is defined by a pair of generally rectangular door leafs which are hinged on the door frame at opposite sides of the doorway for swinging between an open position to permit passage through the doorway and a closed position in which the door leafs are generally coplanar and close the doorway. The door leafs are so dimensioned that there is a substantial vertical gap between the door leafs when they are closed to accommodate convergence of side walls of the passageway. A relatively wide vertical sealing flap is secured to one of the door leafs for overlapping a face of the other door leaf when the door is closed for covering the gap between the door leafs.

Abstract: A mine door system including a door frame to be installed in a mine passageway to define a generally rectangular doorway. A mine door is defined by a pair of generally rectangular door leafs which are hinged on the door frame at opposite sides of the doorway for swinging between an open position to permit passage through the doorway and a closed position in which the door leafs are generally coplanar and close the doorway. The door leafs are so dimensioned that there is a substantial vertical gap between the door leafs when they are closed to accommodate convergence of side walls of the passageway. A relatively wide vertical sealing flap is secured to one of the door leafs for overlapping a face of the other door leaf when the door is closed for covering the gap between the door leafs.

Abstract: A door system for use in a mine stopping comprises a door frame for installation in the stopping to define a doorway, a door hinged to a first side of the door frame for swinging between an open position and a closed position in which the door closes the doorway, and a latch for latching the door in its closed position. The latch comprises a strike which is secured to a second side of the door frame generally opposite the first side and which has a strike plate portion disposed in the doorway in a plane generally perpendicular to the plane of the doorway and spaced from the second side of the door frame thereby to create a void between the strike plate portion and the second side of the doorway. The strike plate portion has a latching aperture therein.

Abstract: A form for making a permanent mine stopping of pourable and hardenable material such as concrete. The form comprises two sets of elongate extension panels, each set including a plurality of panels which may be erected to extend vertically in side-by-side relation from the floor to the roof of a passageway in a mine. When erect, the two sets of panels form two generally vertical walls spaced from one another to define a space to be filled with a pourable and hardenable material to form the stopping. Each panel comprises a pair of elongate sheet metal members having a telescoping sliding fit with one another to permit adjustable extension of the panel to fit the height of the passageway. Tie bars hold the walls of the form in spaced, generally parallel relation prior to, during and immediately after filling of the space between the walls with the pourable and hardenable material.

Abstract: A method and apparatus non-invasively monitor plasma constituent levels. A localized, modified sweating response is induced providing a sweat secretion for analysis of the plasma constituents.

Abstract: A contractible mine stopping adapted to be installed to extend as a vertical wall from the floor to the roof of a passageway in a mine, comprising a series of rows of substantially solid substantially non-compressible blocks of substantially fire-resistant material stacked one on top of another, and at least one row of contractible substantially fire-resistant block-like members adapted to contract without loss of structural integrity when the wall is subjected to a compressive load, as during a convergence of the floor and roof of the passageway. Each block-like member is preferably a hollow metal member which, when subjected to a compressive load, is adapted to contract heightwise of the member a distance corresponding to at least a major portion of the height of the member without loss of structural integrity of the member.

Abstract: A mine door system adapted for installation and a passageway in a mine, comprising a door frame adapted to be installed in the passageway and defining a doorway spaced below a ceiling of the passageway and mine doors hingedly mounted on the door frame for movement between open and closed positions. The system further comprises a top panel structure for substantially closing the space between the door frame and the ceiling of the passageway, the top panel structure being readily contractible heightwise of the passageway without loss of its structural integrity to accommodate a convergence of the ceiling and floor of the passageway without any substantial heightwise deformation of the door frame.

Abstract: A mine door system adapted for installation and a passageway in a mine, comprising a door frame adapted to be installed in the passageway and defining a doorway spaced below a ceiling of the passageway and mine doors hingedly mounted on the door frame for movement between open and closed positions. The system further comprises a top panel structure for substantially closing the space between the door frame and the ceiling of the passageway, the top panel structure being readily contractible heightwise of the passageway without loss of its structural integrity to accommodate a convergence of the ceiling and floor of the passageway without any substantial heightwise deformation of the door frame.

Abstract: A contractible mine stopping adapted to be installed to extend as a vertical wall from the floor to the roof of a passageway in a mine, comprising a series of rows of substantially solid substantially non-compressible blocks of substantially fire-resistant material stacked one on top of another, and at least one row of contractible substantially fire-resistant block-like members adapted to contract without loss of structural integrity when the wall is subjected to a compressive load, as during a convergence of the floor and roof on the passageway. Each block-like member is preferably a hollow metal member which, when subjected to a compressive load, is adapted to contract heightwise of the member a distance corresponding to at least a major portion of the height of the member without loss of structural integrity of the member.

Abstract: A mine door system adapted for installation and a passageway in a mine, comprising a door frame adapted to be installed in the passageway and defining a doorway spaced below a ceiling of the passageway and mine door hingedly mounted on the door frame for movement between open and closed positions. The system further comprises a top panel structure for substantially closing the space between the door frame and the ceiling of the passageway, the top panel structure being readily contractible heightwise of the passageway without loss of its structural integrity to accommodate a convergence of the ceiling and floor of the passageway without any substantial heightwise deformation of the door frame.