A method for continuously detecting carbon deposition in a catalyst bed. Hence, processes involving reactions of carbonaceous materials can be controlled with reference to carbon deposited, thereby avoiding catalyst deterioration and loss of catalyst activity.

In a vehicle detector installation employing an inductive sensing loop that is a frequency determining element of an oscillator, the oscillator is provided with a voltage controlled capacitor as another frequency determining element and is made the voltage controlled oscillator (VCO) of a phase locked loop whereby the VCO is locked to a reference frequency. The presence of a vehicle in the vicinity of the loop causes the capacitor voltage to vary to maintain lock. The varying voltage is applied ...

An apparatus for determining the time of the closest point of approach of a taxiing aircraft comprising a microphone means for producing an input signal in response to the sound energy of a taxiing jet. A low pass filter is provided to receive the input signal and pass low signals having a frequency less than or equal to 1 KHZ while a high pass filter is provided to receive the input signal and pass high signals having a frequency greater than or equal to 1.5 KHZ. Demodulators are provided for r...

The present invention is directed to a detection device comprising: (1) an entrance chamber, (2) a central chamber, and (3) an exit chamber. The central chamber includes an ionizing gas, anode, and means for connecting the anode with an external power supply and pulse counter.

The present invention is directed to a detection system which forms reception beams successively in a series of angular directions. The detection system comprises receiving means for receiving incoming signals in such a manner that the frequency of the incoming signals is varied in accordance with the Doppler effect, and a matched filter for pulse-compressing output signals from said receiving means, with output signals from said matched filter being displayed in an indicator.

A method of uranium exploration employs the detection of radon gas decay products to provide an indication of uranium mineralization. A plurality of collectors of similar surface areas are exposed to soil at or from spaced locations on an exploration site for a time sufficient for the decay products to deposit on the collectors and then, within substantially similar periods following the termination of the exposure, alpha particles, beta particles or gamma rays emitted from the collectors are me...

A method for indicating a defect in a workpiece, comprises applying a continuously variable signal derived from inspection of the workpiece and including a pulse component representative of the defect to a bank of filters having different frequency transmission characteristics respectively representative of defects of different type so that the filter corresponding most closely to the defect inspected, produces a relatively greater output and provides an indication of defect type.

The invention comprises a method and apparatus for the detection, or detection and concentration determination, of nitric oxide in a gas mixture, particularly in tobacco smoke. The apparatus comprises sampling means operable to isolate a predetermined amount of the gas mixture and pass it to a reaction chamber, means for supplying to that chamber a further gas chemiluminescently reactable with the nitric oxide, and detection means responsive to luminescence emitted in the said chamber. The metho...

In a radar system with a plan position indicator, deflecting coil rotation is synchronized with antenna rotation by developing a train of pulses related to antenna rotation for driving a pulse motor controlling coil rotation. Synchronization is achieved by producing a pulse upon a predetermined displacement of the antenna.

The invention provides an apparatus for detecting gases by absorption of infra-red radiation comprising a source of infra-red radiation arranged at one end of an optical path through the apparatus, at the other end of which path there is an infra-red detector. A plurality of cells located within an enclosure housing the cells are arranged to be moved in turn into the optical path in such position that when a cell is positioned on the optical path, the infra-red radiation passes through the cell ...