Abstract: A method and apparatus for depositing thin layers of insulating or slightly conductive materials involves reactive spraying through high-frequency inductive plasma. The conductive component of the material to be deposited is sprayed in a first chamber through which an ionizable inert gas travels, the sprayed particles then passing through a second chamber in which a substrate is placed and to which a reactive gas is supplied.Insulating and weakly inductive materials such as oxides, carbide and nitrides may be deposited at a rate substantially comparable with the rate for conductive materials to obtain high quality uniform deposits.

Abstract: A piezo electric signal generator and receiver assembly for a flaw detector has a generator adjacent to the crystal transducer and a cable connection to a distant point where a d.c. power supply and the indicator is located. The same cable is used for supplying power to the generator and for conveying to the indicator signals corresponding to both acoustic transmitted pulses and reflected returns. For this purpose a charging voltage is applied to a series circuit comprising the capacitor and crystal and this circuit is discharged by a switch connected to the capacitor at the input end of the charging circuit. Both transmitted and received signals are fed in the same direction through the cable and are therefore subjected to the same delays.

Abstract: An automatic sampling device for atmospheric probes to check the propagation of noxious airborne substances. A pump feeds a distributor having a bore therethrough which is pivotably mounted in a circular housing having a plurality of necks extending radially outwardly for the attachment of plastic bags to catch samples of air delivered thereto by the distributor.

Abstract: A method and device for unclogging filter cloths for use in filter apparatus particularly apparatus of the kind wherein the cloth describes a closed loop between a filtering station and an unclogging station.Gas is ejected from one or more nozzles through the cloth which is vibrated at a sonic and/or ultrasonic frequency at a location opposite the nozzle ejection head. The cloth is simultaneously stretched at the same location into a projecting shape having leading and trailing edges with a length, in the direction of motion of the cloth, of not more than three times their height in the direction perpendicular to the direction of motion of the cloth.