A CdZnTe (CZT) crystal provided with a native CdO dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals is disclosed. A two step process is provided for forming the dielectric coating which includes etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and passivating the CZT crystal surface with a solution of 10 w/o NH.sub.4 F and 10 w/o H.sub.2 O.sub...

A method and apparatus for the detection of radioactive material in an area is disclosed. The apparatus comprises a transmitter operatively arranged to transmit electromagnetic radiation, a receiver operatively arranged to measure an intensity of the electromagnetic radiation, and processing means operatively arranged to determine the presence of radioactive material based on the intensity measurement. Two receiver configurations are possible. In the first, the receiver measures the intensity of...

A photodiode detector assembly for use with an ionizing radiation detector, the assembly includes a first layer having a first side and a second side and an array of backlit photodiodes disposed at the second side, and a second layer disposed proximate to and opposing the second side of the first layer. The second layer includes thru vias. Light rays entering the first layer at the first side and impinging the backlit photodiodes at the second side result in electrical signals at the thru vias o...

An air-ionizing and deozonizing electrode block is fixed at the center of an insulating shell. The electrode block is made of a material containing manganese dioxide or copper oxide. The electrode block has many uniformly distributed perforations parallel to the axis of the insulating shell. Each perforation contains a conductive needle with its end bent 90.degree. and fixed on the rear of the electrode block by conductive material. The point of the conductive needle in the central perforation o...

Apparatus for ionizing air, for example for feeding to a boiler to act as a catalyst, comprises a closed container (15) which is divided into two chambers (17, 18). Water is fed under pressure to atomizing jets (21,22) which produce a mist inside each chamber. Air is fed by a pump (28) into the first chamber and passes upwards through the mist in that chamber, through an aperture (20) near the top of a partition wall (19) and downwards through the mist in the second chamber. The thus-ionized air...

An ionization chamber for producing oxygen ions, preferably positive oxygen ions, without substantial ozone formation. The housing can be composed of polyvinyl chloride or another insulating material and the ionization electrodes can include a cathode wire closed to the inlet and an anode wire downstream from the cathode wire, the wires extending transverse to the oxygen flow direction.

In an apparatus which produces and delivers water vapor upon the skin of an animate subject for dermatological purposes, circuitry monitors the fluid level of a heated container and disables the heating element thereof. When the water level drops, resistance in a temperature sensitive device drops disabling voltage to the heating element via the control circuitry. The control circuit cuts off power to the heating element and is capable of producing a warning signal. Also provided in combination ...

A dosimeter is described that does not show differences in sensitivity over its sensitive area when the ambient pressure changes. To that purpose the measuring chamber and a pressure compensation element together form a single gas tight chamber having at least partially of slack material, wherein the pressure inside the measuring chamber is essentially equal to ambient pressure such that no mechanical distortion of the measuring chamber over its sensitive area takes place.

A device for detecting ionizing radiation emanating from a plurality of samples, said device comprising: a receptacle having a planar surface and provided with a plurality of recesses each for holding a respective sample, each said recess being open at said surface; a cover member having at least one planar electrically conductive member provided with openings, said conductive member being spaced from said receptacle and being disposed parallel to said planar surface; and a voltage source connec...

An air ionizing cell has an elongated, hollow dielectic cylindrical body member, one end of which defines a greatly restricted orifice (relative to the inside diameter of the cylindrical body member). An elongated metallic electrode having an end tapered at a constant rate and terminating at a microscopically sharp point is disposed coaxially within the cylindrical body member. The point of the electrode is positioned concentrically within the orifice and an electrical potential is applied to th...