Abstract: A grid pattern for a solar cell of the type including a semiconductive layer doped to a first polarity and a top counter-doped layer. The grid pattern comprises a plurality of concentric conductive grids of selected geometric shapes which are centered about the center of the exposed active surface of the counter-doped layer. Connected to the grids is one or more conductors which extend to the cell's periphery. For the pattern area, the grids and conductors are arranged in the pattern to minimize the maximum distance which any injected majority carriers have to travel to reach any of the grids or conductors. The pattern has a multi-axes symmetry with respect to the cell center to minimize the maximum temperature differentials between points on the cell surface and to provide a more uniform temperature distribution across the cell face.

Abstract: A method of forming a tubular wick for a heat pipe. The method is characterized by the steps of forming a wick blank of a predetermined thickness comprising a plurality of superimposed layers of stainless steel mesh screen, wet rolling the blank for reducing the thickness thereof, wrapping the blank about an inner mandrel, compressing the blank into a rigid tubular structure, removing the tubular structure from the mandrel and sintering the tubular structure.

Abstract: A continuous HCl in-air indicator consists of a tube-like element with an inlet end through which a continuous stream of air, containing HCl, enters. The air flows downstream from the inlet end and exits the element's outlet end. Positioned between the element's inlet and outlet ends are first and second spaced apart photoelectric units, which are preferably positioned adjacent the inlet and outlet ends, respectively. Ammonia gas is injected into the air, flowing through the element, at a position between the two photoelectric units. The ammonia gas reacts with the HCl in the air to form ammonium chloride particles. The difference between the outputs of the two photoelectric units is an indication of the amount of HCl in the air stream.

Abstract: Trap densities in dielectric films can be determined by tunnel injection measurements when the film is incorporated in an insulated-gate field-effect transistor (IGFET). Under applied bias to the transistor gate, carriers (electrons or holes) tunnel into traps in the dielectric film. The resulting space charge tends to change channel conductance. By feeding back a signal from the source contact to the gate electrode, channel conductance is held constant, and by recording the gate voltage as a function of time, trap density can be determined as a function of distance from the dielectric-semiconductor interface. The process is repeated with the gate bias voltage at different levels in order to determine the energy distribution of traps as a function of distance from the interface.

Abstract: A gear head wrench particularly suited for use in applying torque to bolts without transferring torsional stresses to bolt-receiving structures. The wrench is characterized by a coupling including a socket, for connecting a bolt head with a torque multiplying gear-train, provided within a housing having an annulus concentrically related to the socket and adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. As a result of the foregoing, the operator of the wrench is substantially isolated from any forces which may be imposed.

Abstract: An atmosphere sampler includes a very thin filter element with straight-through holes on the order of 1.mu.. A sample of air with particles to be examined is driven by means of a pressurized low molecular weight gas, e.g., He to the filter element front side. A partial vacuum may be present at the back side of the filter element. The pressure differential across the filter element is just below the rupture point of the filter element. By admixing a low molecular weight gas as the carrier gas with the air sampler the velocity with which the air sample is driven to the filter element is maximized for the particular pressure differential across the filter element, so that at least some particles with diameters less than the hole diameter do not follow changes in the air stream line direction as it passes through the filter element holes and therefore the smaller diameter particles are deposited on the filter element. When using a filter element of plastic material of a thickness on the order of 10.mu.

Abstract: A miniature transducer for sensing muscle displacement substantially consists of a curved beam of high elastic compliance connected at its ends to two prongs. The prongs have sharpened tips which are insertable into the muscle under observation. A sensitive strain gauge is bonded to the beam preferably at the point of greatest curvature. The strain gauge output is directly related to changes in the beam curvature. As the muscle under observation expands the spacing between the prongs increases which decreases the beam curvature. On the other hand, when the muscle contracts the prongs' spacing decreases, thereby increasing the beam curvature.