Abstract: A measuring device for measuring in an ear canal includes a probe for insertion into an ear canal having an opening for letting air in to and out of the ear canal, and a pump for providing a pressure above a surrounding atmospheric pressure or below the surrounding atmospheric pressure, the pump including a housing with openings for inlet and/or outlet, where within the housing a piston element having piezo electric properties is disposed, one opening in the pump being operatively connected to the opening in the probe.

Abstract: The invention relates to an apparatus for determining the pressure drop over the nose of a patient during breathing and determining the opening pressure for the patients Eustachian tube. The apparatus comprises a measuring tube having a proximal end for connecting to a patients nose and a distal end leading to the surrounding atmosphere, a measuring gate, flow measuring means for measuring air flow in the measuring tube, first pressure measuring means for measuring the pressure in the tube proximal end and second pressure measuring means for measuring the pressure at the measuring gate. According to the invention the apparatus comprises means for generating a sound signal in the tube proximal end, or means for generating a sound signal at the measuring gate and means for receiving sound signals in the tube proximal end. The invention further relates to a method for measuring the above mentioned pressure drop.

Abstract: The invention relates to an apparatus for measuring cross sections in a patient's right and left nose cavity in the cavity behind the nose separation (epipharyn), and in the throat (oropharynx), and for detecting the opening of the Eustachian tube. The apparatus comprises an electro-acoustic sound emitter, a first transmission tube leading from the emitter to a first connecting piece, connecting means for connecting the first connecting piece to a patient's one nostril, a proximal microphone located adjacent the emitter and/or a first microphone built into the first connecting piece, and a computer for generating electrical signals for the emitter and for sampling and analyzing electrical signals from the microphone or microphones. According to the invention the apparatus further comprises a preferably releasable second acoustic transmission tube leading from the emitter in an opposite direction of the first acoustic transmission tube, hereby constituting an elongation of this pass the emitter.

Abstract: The present invention relates to a process for production of chlorine dioxide by reacting in a reaction vessel an alkali metal chlorate, sulfuric acid and a reducing agent, preferably methanol, in proportions to generate chlorine dioxide in a reaction medium maintained at a temperature from about 50.degree. C. to about 100.degree. C. and an acidity within the interval from 4.8 to 11 N and subjected to a subatmospheric pressure sufficient to effect evaporation of water. A mixture of chlorine dioxide and water vapour is withdrawn from an evaporation region in the reaction vessel and alkali metal sulfate is precipitated in a crystallization region in the reaction vessel. The alkali metal sulfate, which is an alkali metal sesquisulfate, from the crystallization region is heated to the formation of gaseous sulfur trioxide and a neutral alkali metal sulfate. The gaseous sulfur trioxide is absorbed in water to the formation of sulfuric acid.