An auto-ranging ac resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an ac excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance.

The disclosure is directed to an acoustical heat pumping engine without moving seals. A tubular housing holds a compressible fluid capable of supporting an acoustical standing wave. An acoustical driver is disposed at one end of the housing and the other end is capped. A second thermodynamic medium is disposed in the housing near to but spaced from the capped end. Heat is pumped along the second thermodynamic medium toward the capped end as a consequence both of the pressure oscillation due to the driver and imperfect thermal contact between the fluid and the second thermodynamic medium.

Americium is separated from mixtures containing plutonium, other actinides, and other non-lanthamide impurities, by a combined process of anion exchange resin sorption to remove plutonium, and a bidentate organophosphorus solvent extraction of americium of the anion exchange resin effluent. Dihexyl-N,N-diethylcarbamylmethylenephosphonate is a preferred solvent. The initial mixture may be subjected to a cation exchange operation to remove monovalent impurities. The process is especially effective when aluminum, zinc, lead, and copper are present in significant quantities in the original mixture.

A technique for pyrolyzing biomass materials is disclosed wherein a hot surface is provided having a predetermined temperature which is sufficient to pyrolyze only the surface strata of the biomass material without substantially heating the interior of the biomass material thereby providing a large temperature gradient from the surface strata inwardly of the relatively cool biomass materials. Relative motion and physical contact is produced between the surface strata and the hot surface for a sufficient period of time for ablative pyrolyzation by heat conduction to occur with minimum generation of char.

A device is described for indicating and preventing damage to voltage cells such as galvanic cells and fuel cells connected in series by detecting sequential voltages and comparing these voltages to adjacent voltage cells. The device is implemented by using operational amplifiers and switching circuitry is provided by transistors. The device can be utilized in battery powered electric vehicles to prevent galvanic cell damage and also in series connected fuel cells to prevent fuel cell damage.

An on-line, nonreferenced apparatus for measuring the concentration of a biomarker species in authentic biological samples in solution comprises conduit means for conducting said sample solution from a source of said solution, stream diversion means disposed within the conduit for diverting a predetermined amount of said sample for analysis, means for introducing and independently regulating the flow of one or more reactants disposed in fluid communication with said diverted stream, incubating means within the diverted stream for reacting said reactants and biomarkers to produce a bioluminescence emission, and means disposed within the diverted stream for monitoring said emission intensity which is correlatable to said biomarker concentration.

It is therefore an object of the present invention to provide a capacitively-coupled inductive shunt current sensor. To achieve the other object, and in accordance with the purpose of the present invention, as embodied and broadly described herein, the apparatus of this invention may comprise a capacitively coupled inductive shunt current sensor comprising: annular inductive channel means formed in a conductor carrying a high voltage pulsed current; an electrode capacitively coupled to said conductor on opposite sides of said annular inductive channel means; voltage dividing capacitor means connected in series with said electrode for reducing the magnitude of the detected output signal; output coupling means connected to said voltage dividing capacitor means for producing an output signal representative of said high voltage pulsed current.

A data transmission system is disclosed which includes a transmission medium which has a certain propagation delay time over its length. A number of data stations are successively coupled to the transmission medium for communicating with one another. Each of the data stations includes a transmitter for originating signals, each signal beginning with a carrier of a duration which is at least the propagation delay time of the transmission medium. Each data station also includes a receiver which receives other signals from other data stations and inhibits operation of the transmitter at the same data station when a carrier of another signal is received.

A catalytic cartridge internally heated is utilized as a SO/sub 3/ decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO/sub 3/ gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube being internally heated. In the axial-flow cartridge, SO/sub 3/ gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and being internally heated. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety.

The present invention is directed to a method for making a wide variety of general-purpose cermets and for radioactive waste disposal from ceramic powders prepared from urea-dispersed solutions containing various metal values. The powders are formed into a compact and subjected to a rapid temperature increase in a reducing atmosphere. During this reduction, one or more of the more readily reducible oxides in the compact is reduced to a selected substoichiometric state at a temperature below the eutectic phase for that particular oxide or oxides and then raised to a temperature greater than the eutectic temperature to provide a liquid phase in the compact prior to the reduction of the liquid phase forming oxide to solid metal. This liquid phase forms at a temperature below the melting temperature of the metal and bonds together the remaining particulates in the cermet to form a solid polycrystalline cermet.

Coal hydrogenation vessel has hydrogen heating passages extending vertically through its wall and opening into its interior.

A vessel system comprises an outer shell of carbon fibers held in a binder, a coolant circulation mechanism and control mechanism and an inner shell comprised of a refractory material and is of light weight and capable of withstanding the extreme temperature and pressure environment of, for example, a coal gasification process. The control mechanism can be computer controlled and can be used to monitor and modulate the coolant which is provided through the circulation mechanism for cooling and protecting the carbon fiber and outer shell. The control mechanism is also used to locate any isolated hot spots which may occur through the local disintegration of the inner refractory shell.

A multiple laser having one or more gaseous laser stages and one or more free electron stages is described. Each of the free electron laser stages is sequentially pumped by a microwave linear accelerator. Subsequently, the electron beam is directed through a gaseous laser, in the preferred embodiment, and in an alternative embodiment, through a microwave accelerator to lower the energy level of the electron beam to pump one or more gaseous lasers. The combination laser provides high pulse repetition frequencies, on the order of 1 kHz or greater, high power capability, high efficiency, and tunability in the synchronous production of multiple beams of coherent optical radiation.

A combination regenerative ring and backward Raman waveguide amplifier and a combination regenerative ring oscillator and backward Raman waveguide amplifier which produce Raman amplification, pulse compression, and efficient energy extraction from the CO/sub 2/ laser pump signal for conversion into a Stokes radiation signal. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman waveguide amplifier. The backward Raman waveguide amplifier configuration extracts a major portion of the remaining energy from the CO/sub 2/ laser pump signal for conversion to Stokes radiation.

A surge counter for a rotating compressor is provided which detects surging by monitoring the vibration signal from an accelerometer mounted on the shaft bearing of the compressor. The circuit detects a rapid increase in the amplitude envelope of the vibration signal, e.g., 4 dB or greater in less than one second, which is associated with a surge onset and increments a counter. The circuit is rendered nonresponsive for a period of about 5 seconds following the detection which corresponds to the duration of the surge condition. This prevents multiple registration of counts during the surge period due to rapid swings in vibration amplitude during the period.

A conductor and method of making the conductor are provided for use in winding electrical coils which are cooled by a fluid communicating with the conductor. The conductor is cold worked through twisting and reshaping steps to form a generally rectangular cross section conductor having a plurality of helical cooling grooves extending axially of the conductor. The conductor configuration makes it suitable for a wide variety of winding applications and permits the use of simple strip insulation between turns and perforated sheet insulation between layers of the winding.

A continuous chain bit for hard rock drilling is disclosed which is capable of downhole cycling. A drill head assembly moves axially relative to a support body while the chain on the head assembly is held in position so that the bodily movement of the chain cycles the chain to present new composite links for drilling. A pair of spring fingers on opposite sides of the chain hold the chain against movement. The chain is held in tension by a spring-biased tensioning bar. A head at the working end of the chain supports the working links. The chain is centered by a reversing pawl and piston actuated by the pressure of the drilling mud. Detent pins lock the head assembly with respect to the support body and are also operated by the drilling mud pressure. A restricted nozzle with a divergent outlet sprays drilling mud into the cavity to remove debris. Indication of the centered position of the chain is provided by noting a low pressure reading indicating proper alignment of drilling mud slots on the links with the corresponding feed branches.

The present invention is directed to a fuel-air control system for a combustor in which coal-derived gas of varying heat content is used. To maintain the temperature in the combustor at an essentially constant value the fuel-to-air ratio is adjusted by using a temperature actuated variable pressure regulator in the gas feed line to compensate for the variability of the heat content of the gas. The velocity of the products of combustion is maintained at an essentially constant flow rate by controlling the mass flow of the air and fuel through linked valves on the gas and air feed lines.

A load switching circuit for switching two or more transformer taps under load carrying conditions includes first and second parallel connected bridge rectifier circuits which control the selective connection of a direct current load to taps of a transformer. The first bridge circuit is normally conducting so that the load is connected to a first tap through the first bridge circuit. To transfer the load to the second tap, a switch is operable to connect the second bridge circuit to a second tap, and when the second bridge circuit begins to conduct, the first bridge circuit ceases conduction because the potential at the second tap is higher than the potential at the first tap, and the load is thus connected to the second tap through the second bridge circuit. The load switching circuit is applicable in a motor speed controller for a wound-rotor motor for effecting tap switching as a function of motor speed while providing a stepless motor speed control characteristics.

A system for monitoring coolant conditions within a pressurized vessel is described. A length of tubing extends outward from the vessel from an open end containing a first line restriction at the location to be monitored. The flowing fluid is cooled and condensed before passing through a second line restriction. Measurement of pressure drop at the second line restriction gives an indication of fluid condition at the first line restriction. Multiple lengths of tubing with open ends at incremental elevations can measure coolant level within the vessel.

A detonator-activated ball shutter for closing an aperture in about 300 ..mu..seconds is disclosed. The ball shutter containing an aperture through which light, etc., passes, is closed by firing a detonator which propels a projectile for rotating the ball shutter, thereby blocking passage through the aperture.

An improved downhole steam injector has an angled water orifice to swirl the water through the device for improved heat transfer before it is converted to steam. The injector also has a sloped diameter reduction in the steam chamber to throw water that collects along the side of the chamber during slant drilling into the flame for conversion to steam. In addition, the output of the flame chamber is beveled to reduce hot spots and increase efficiency, and the fuel-oxidant inputs are arranged to minimize coking.

The invention is a dust feed device for delivery of a uniform supply of dust for long periods of time to an aerosolizing means for production of a dust suspension. The device utilizes at least two tandem containers having spiral brushes within the containers which transport the dust from a supply to the aerosolizer means.

A secondary electrochemical cell is described with the positive and negative electrodes separated by a molten salt electrolyte with the negative electrode comprising a particulate mixture of lithium-aluminum alloy and electrolyte and an additive selected from graphitized carbon, Raney iron or mixtures thereof. The lithium-aluminum alloy is present in the range of from about 45 to about 80% by volume of the negative electrode, and the electrolyte is present in an amount not less than about 10% by volume of the negative electrode. The additive of graphitized carbon is present in the range of from about 1 to about 10% by volume of the negative electrode, and the Raney iron additive is present in the range of from about 3 to about 10% by volume of the negative electrode.