Abstract: A retaining device for connecting a tool head with a tapered eye to a tapered tongue of a tool handle. The retaining device includes two threaded, J-shaped bolts, a V-shaped plate having a hole in each leg for receiving the threaded portion of a J-bolt, and two hex nuts. The V-plate is positioned on the outer surface of the tongue with the J-bolts extending through the eye and latching a lower surface of the tool head. When the nuts are threaded onto the J-bolts and tightened, the J-bolts are drawn upwardly and radially outwardly, forcing the tool head into a secure, wedged engagement with the tool handle.

Abstract: A method for treating waste fluids to remove selected chemicals such as minerals and metals wherein a bacterial culture that will attach to a selected chemical is transferred to a nutrient medium for a time period sufficient to produce satisfactory bacterial cell growth. The bacterial cells are then attached to a porous fiber webbing supported in a suitable container and the nutrient medium is then withdrawn from the container and waste fluid introduced into the container for a period of time sufficient to attach the chemical to the bacterial cells. The waste fluid is then removed from the container and the chemical separated from the fiber webbing.

Abstract: A photochemical reactor is divided into a first section suitable for containing a volume of fluid to be reacted and a second section having at least one light transmitting wall. A porous, high area, fiber webbing is mounted within the reactor so that at least a portion of the webbing is immersed in the fluid. The webbing is moved within the reactor so that the webbing is sequentially immersed in the fluid contained in the first reactor section and then moved to the second reactor section whereat the fluid attached to the webbing is exposed to light transmitted through the light transmitting wall.

Abstract: A catalytic heat exchanger useful for carrying out a catalytic reaction wherein a gaseous or vaporized mixture is flowed into contact with a catalytic material reactive with such mixture. The heat exchanger includes a reaction zone divided by a plurality of baffle plates into regions of progressive increasing or decreasing volume. The baffle plates form a tortuous flow path for the gaseous or vaporized mixture that provides intermittent contact with a bundle of heat exchange tubes and the catalytic material. The intermittent contact in turn provides a uniform reaction temperature which promotes reaction specificity.

Abstract: A method and apparatus particularly useful for producing alcohols such as ethanol from sugars such as glucose. The apparatus comprises a container for holding a selected nutrient solution, a substrate comprising a multiplicity of fibers suitable for supporting a selected converting organism supported within the container and means for moving one of the substrate and the nutrient solution relative to the other at a speed slightly below that at which the organism becomes detached from the substrate while maintaining sufficient contact time between the nutrient solution and the converting organism to produce a satisfactory yield.

Abstract: An electric heat storage apparatus comprises an electric heating element, a ceramic heat storage pipe, an air passageway in communication with the pipe, and a thermostatically controlled air circulation means. The ceramic pipe has a scalloped-shaped outer surface providing a plurality of crests and troughs and a series of parallel grooves cut in at least some of the crests. The heating element is located in the grooves in contact with the pipe. In a preferred embodiment, the pipe is provided with a plurality of internal ribs of at least two different lengths. The pipe is supported on a ceramic cradle and a ceramic sponge or metal turnings are inserted into the pipe between the ribs to increase the heat transfer area.

Abstract: A bipolar transistor logic circuit comprises an input terminal for receiving digital logic signals, an output terminal, an output driver including a current sink transistor and a current source transistor, and a control stage coupled between the input terminal and the output driver. When the control stage is nonconducting, the current source transistor is turned ON and the current sink transistor is turned OFF providing a first digital logic signal at the output terminal. When the control stage is conducting, the current source transistor is initially turned OFF and the current sink transistor is turned ON providing a second digital logic signal at the output terminal. If the output load does not provide the amount of current required by the current sink transistor, the current source transistor is turned ON by the control stage and provides the current sink transistor with collector current to prevent the sink transistor from saturating.

Abstract: An analyzer for biological fluids includes a sample fluid metering device that is movable to a first metering position located directly over a generally planar test element supported in a metering station, and a reference fluid metering apparatus that is movable to a second metering position closely adjacent the first metering position. The reference fluid metering apparatus comprises a reference fluid supply reservoir supported in a location spaced from the metering station, an aspirator operable to aspirate reference fluid from the reservoir and to deposit the fluid on the test element positioned at the metering station and a cam and gear arrangement driven by a single drive motor for moving the aspirator linearly toward and away from the supply reservoir and toward and away from the metering station and for pivotally moving the aspirator between a position spaced from the supply reservoir and a position spaced from the metering station.

Abstract: Exposure control apparatus for a camera having an objective lens, an unregulated, fixed output flash device which, in the absence of ambient light, provides one-half stop of underexposure of a photographic subject located at the near limit acceptable image focus point of the lens, and a mechanism for automatically controlling an exposure in accordance with the intensity of the ambient light. In a flash exposure mode, the mechanism is operated to produce an exposure which, in the absence of artificial illumination, would provide one-half stop of underexposure of the photographic subject. The total exposure, flash plus ambient, is within .+-. one-half stop of a nominally correct exposure throughout the useable depth of field of the camera lens.

Abstract: A photographic camera includes exposure control apparatus for determining automatically if the camera is adjusted to achieve a suitable exposure. This determination is made taking into account the exposure latitude of film in the camera. The control apparatus includes film data-retrieval apparatus for receiving both film speed and film exposure latitude data. A light-level sensing circuit determines scene brightness, and diaphragm and shutter control mechanisms provide data relating to the aperture size and shutter speed, respectively, at which the camera is set. A microprocessor computes an exposure value that is based on scene brightness and film speed. The microprocessor then uses the computed exposure value to compute a range of acceptable exposure values corresponding to the film exposure latitude. The microprocessor also computes an exposure value that is anticipated based on the aperture size and shutter speed at which the camera is set.

Abstract: A roll film and a photographic camera cooperate to facilitate automatic attachment of the film to a rotatable film take-up spool. The roll film has a leader portion provided with a novel connecting aperture that includes a flexible tongue element which extends forwardly into the aperture. The camera includes a rotatable film take-up spool which is provided with a capturing member having a head surface, a leading edge surface and a trailing edge surface provided with a recess. The leading edge surface of the film capturing means engages the film aperture upon rotation of the take-up spool and the head surface flexes the tongue element sufficiently to allow the head surface to pass through the plane of the film. Further rotation of the take-up spool allows the tongue element to snap back into the trailing edge recess of the capturing member to secure the film to the take-up spool.

Abstract: A method for producing visible images in certain charge sensitive, dry processable recording elements. Image recording is accomplished by flowing, in a resistive recording element containing a reducible metal compound, an imagewise pattern of electrical current of sufficient magnitude to produce therein a storable latent image. The metal compound in the latent image areas is subsequently reduced by a dry development technique to produce a visible image.

Abstract: A recording process is disclosed in which an X-ray sensitive photoconductive element exhibiting persistent conductivity and a charge sensitive, dry processable recording material are sandwiched between a pair of electrodes. A source of potential is applied across the electrodes and the photoconductive element is briefly exposed to an imagewise pattern of X-ray radiation forming a latent image in the recording material. Allowing the current to continue to flow through the sandwich after the X-ray exposure is terminated increases the sensitivity of the recording process by a factor of up to 100. The latent image is then amplified and rendered visible by uniformly heating the entire recording material.

Abstract: Apparatus for measuring the surface potential of moving electrostatically charged elements uses at least one electrically conducting detector mounted on the outer periphery of a grounded roller. An insulated ring secured around each end of the roller in an edge contacting relationship with the charged element under measurement provides a friction drive for the roller and maintains the detector in a spaced and non-contacting position from the charged element. As the roller is rotated, the detector is alternately exposed to the charged element and to a grounded shell arranged in a spaced and non-contacting manner from both the charged element and the roller and builds an A.C. voltage on a sampling capacitor. The output of the sampling capacitor is connected to a circuit which determines the envelope of the A.C. voltage and provides a differential D.C. voltage representative of the surface potential of the charged element. This D.C.