Abstract: Apparatus to permit the correction of a single bit error occurring in a sequence of data packets (e.g. bytes) comprising data bits. An encoder produces an error correction packet (e.g. byte), the value of which is determined algebraically from the value of bits in the data sequence. All data packets and the error correction packet have a predetermined parity. A decoder receives the sequence of data packets and error correction packet. If a single bit error in the data bits has occurred during transmission, one data packet is identified as having in it the bit in error. Algebraically, the data bit in error is identified and corrected.

Abstract: There is described a system for producing noise particularly for sonic testing of an article, such as a satellite, in a reverberation chamber. In one of its aspects the system comprises a low frequency high-level broad-band noise source; a tube means including a section formed as an acoustic horn connected at its small end to the low frequency source and at its large end to the chamber. A Hartmann-type air acoustic high level noise generator, or generators are located inside the tube at a predetermined position. In operation the generator is excited by the generated low frequency noise to provide an output of non-linearly modulated noise. Also described is a Hartmann-type noise generator which comprises a nozzle and an aligned acoustic tube spaced therefrom by an air gap. A reverberation cup is formed in the mouth of the tube facing the nozzle and a bridge member extends between the nozzle and tube and spans the air gap.

Abstract: A microwave applicator for heating materials with microwaves. A coaxial transmission line is inserted in the material and coupled at one end to a source of microwaves. A shorting plate covers the other end of the cable and a plurality of radiating apertures are provided along the outer conductor. The use of a coaxial line avoids the minimum size requirements present with hollow waveguides. The coaxial line may be directly coupled to the output probe of a microwave generator by means of spring-finger contacts on the inner conductor of the coaxial line.

Abstract: An atomizer (14) for producing a finely dispersed spray (16) of a solid-liquid slurry (18) includes a mixing body (22) having an internal mixing chamber (28) and a spray outlet passage (30). The flow cross-section of the mixing chamber (28) is elongated in shape, with an atomizing medium inlet passage (24) for injecting an atomizing medium (20) into the mixing chamber (28) co-linearly with the spray outlet passage (30). The slurry inlet passage (26) injects the slurry (18) into the mixing chamber (28) at an angle (32) oblique to the flow of atomizing medium and perpendicular to the mixing chamber flow cross-section elongation.

Abstract: A process is described for removing both high polar and neutral nitrogen compounds from petroleum processing liquid products and petroleum distillate fractions. According to the novel feature, a chlorosilylated silica gel is used as adsorbent for the nitrogen compounds. This adsorbent has been found to be superior to regular silica gel and commercial ion exchange resins for removing particularly the neutral nitrogen compounds.

Abstract: Semiconductive photoanodes formed of titanium dioxide (TiO.sub.2) are known for use in photoelectrochemical cells. They have been made by various techniques, including chemical vapor deposition, thermal oxidation or anodic oxidation of thin titanium foils, hot pressing of TiO.sub.2 powder, and plasma spraying. The present invention provides a method for the fabrication of TiO.sub.2 thick film photoanodes, which method is simple, inexpensive and suitable for mass production of large area plates. The method comprises screen printing a film of conductive material on a clean alumina substrate which is then heated to fuse the conductive material into a conductive layer. A first layer of TiO.sub.2 particles in an organic carrier is then screen-printed over the conductive layer, at least 10% of the TiO.sub.2 being of anatase form. The structure is then heated to burn off the organic carrier and to transform at least part of the TiO.sub.2 from anatase form to rutile form, this resulting in good adhesion of the TiO.