Abstract: For use in a pulsed-laser lidar such as a laser ceilometer, there are shown several examples of signal processing means for separating desired pulses due to targets such as clouds from strong background signals due to suspended particles causing poor visibility. The several examples belong to a class of means having the property of applying, to an electrical signal pulse waveform, a time-distributed signed electrical weighting function having negligible total weight, with alternations of sign of weights separated by intervals of the order of the width of the desired pulses.

Abstract: A process and apparatus for gasification of carbonaceous matter, preferably coal, is disclosed. In one embodiment, a stream of previously produced char, preferably produced from coal or other fuel, together with an oxidizer and steam is introduced into a combustion stage. The combustion gas produced by the combustion passes into a mixing zone and thence with high turbulence into a gasification zone or stage at subsonic velocity. Pulverized carbonaceous matter, preferably coal, is introduced and dispersed in the combustion gas in the mixing zone. The temperature, velocity and velocity changes principally of the gas in the gasification zone or stage are controlled to provide a heating rate for the particles of pulverized carbonaceous matter of at least about 10.sup.5 degrees Kelvin per second, and to effect rapid removal of volatile components from the immediate vicinity of the particles.

Abstract: A process and apparatus for gasification of carbonaceous matter, preferably coal, is disclosed. A stream of previously produced char, preferably produced from coal, or other fuel together with an oxidizer and steam is introduced into a first or combustion stage. The combustion gas produced by the combustion passes into a second or gasification stage and through a nozzle at at least sonic velocity. Pulverized carbonaceous matter, preferably coal, is introduced and dispersed in the combustion gas in the gasification stage. The temperature, velocity and velocity changes principally of the gas in the gasification stage are controlled to provide a heating rate for the particles of pulverized carbonaceous matter of at least about 10.sup.5 degrees Kelvin per second, and to effect rapid removal of volatile components from the immediate vicinity of the particles.

Abstract: A fluidic amplifier or switch for supplying pulses of a power gas to be controlled which is insensitive to load impedance or back pressure. One arm of the fluidic switch comprising part of the gas injection path is coupled to a working outlet and the other arm is coupled through a sonic orifice to a vent outlet. An orifice is provided in the downstream end of the power gas injection path, the injection pressure is maintained at preferably at least about twice the maximum back pressure and a substitute gas is injected into the arm of the fluidic switch not carrying the power gas to be controlled. The two gases are each alternately supplied to the working outlet and the vent outlet. When the power gas to be controlled is supplied to the working outlet, the substitute gas is supplied to the vent outlet and when the substitute gas is supplied to the working outlet, the power gas to be controlled is supplied to the vent outlet to maintain the pressure constant across the working outlet orifice.

Abstract: A high repetition rate high power spark gap switch of the type useful in pulsed lasers, radar systems and pulse-forming networks is enabled to operate with higher switching speed at high power levels by rapid chemical composition change cyclically made in the spark gap at high frequency with differing standoff voltage capabilities of different compositions produced in the gap in each cycle. The different standoff voltage capabilities are produced by injecting different gases under fluidic switching control.

Abstract: Improved electron beam driven gas laser method and apparatus with the achievement of high single pulse energies therefore enabled by establishment of a magnetic field in a direction substantially parallel to the desired direction of electron beam propagation into a gas. The applied magnetic field is made substantially uniform and sized to exceed that of the self induced magnetic field of the current established by the electron beam, alone or in combination with a discharge current (optionally) established in the gas.

Abstract: A process of cutting thick metal workpieces wherein a cutting laser beam is inclined back from a cutting direction and oscillated in a direction parallel with the cutting direction while a gas jet is directed from above the workpiece at an angle approximately normal to the direction of the laser beam incident on the workpiece to blow away the laser melted material as it is produced.

Abstract: A metal layer is clad to a metal substrate by laying spaced rods or wires of a cladding metal on the substrate surface and scanning the cladding metal with a continuously operating laser beam, part of which impinges directly on the cladding metal to melt it and part of which impinges on the adjacent surface area of the substrate to improve flow of molten metal thereon. The cladding metal may be fed to the substrate surface in synchronism with laser beam scanning. The process produces a clad layer of the cladding metal on the substrate characterized by a fine and homogeneous structure within the clad on layer and further characterized by uniform and high hardness compared to prior art cladding methods. The surface of the clad may be smoothed by locally oscillating the laser beam during the course of cladding and/or by multiple passes.