Abstract: A gas cleaning apparatus includes: an ion source to provide an ion beam, a charging zone to form charged particles by exposing particles of a particle-laden gas to the ion beam, and a filter element to collect the charged particles, wherein the ion source includes a corona electrode to generate ions by a corona discharge, the ion source is arranged to form the corona discharge in a protective gas, and wherein the apparatus is arranged to form the ion beam by using an electric field to draw the generated ions from the corona discharge to the particle-laden gas.

Abstract: A process for measuring particle concentrations in a gas using an ejector for producing an essentially constant sample flow and for efficient mixing of the particle-containing sample and essentially clean, ionized gas. The invention also relates to an apparatus implementing such process. The process and the apparatus can be utilized for example in measuring particle concentrations in an exhaust system of a combustion engine.

Abstract: A method and apparatus for controlling a vapor deposition based coating process, including monitoring ultrafine particles, and adjusting at least one process parameter based on the monitoring. During at least one stage of the coating deposition process, at least one of the coating precursors includes a gas, a vapor, or an aerosol.

Abstract: Method and apparatus for controlling a coating deposition process, where at least at one stage of the coating deposition process at least one of the coating precursors includes a gas, a vapour or an aerosol. The method includes monitoring ultrafine particles and adjusting at least one process parameter based on the monitoring. The apparatus includes means for monitoring ultrafine particles and means for adjusting at least one process parameter based on the monitoring.

Abstract: A process for measuring particle concentrations in a gas using an ejector for producing an essentially constant sample flow and for efficient mixing of the particle-containing sample and and essentially clean, ionized gas. The invention also relates to an apparatus implementing such process. The process and the apparatus can be utilized for example in measuring particle concentrations in an exhaust system of a combustion engine.

Abstract: A method and a sensor device for determining particle emissions from exhaust gases of a combustion engine substantially during the use in an exhaust pipe system or a corresponding exhaust gas duct, in which method emitted particles contained in the exhaust gases are charged and the particle emissions are determined by measuring the electric charge carried by the emitted particles in the exhaust gas duct. The emitted particles are charged by varying the way of charging or the charging power with respect to time in such a manner that as a result of the charging, emitted particles brought into at least two different electrical charge states are present, wherein the charge of the emitted particles is further determined as a difference value/values measured from the emitted particles brought into said at least two different electrical charge states.

Abstract: The invention relates to a device (30) for determining the size distribution of aerosol particles from a flow (11), the device (30) comprising an electric mobility analyzer (10) and an impactor (20), connected to each other in such a way that the nozzle part (22a) of the first stage of the impactor (20) is simultaneously the bottom plate of said mobility analyzer (10).

Abstract: A method and a sensor device for determining particle emissions from exhaust gases of a combustion engine substantially during the use in an exhaust pipe system or a corresponding exhaust gas duct, in which method emitted particles contained in the exhaust gases are charged and the particle emissions are determined by measuring the electric charge carried by the emitted particles in the exhaust gas duct. The emitted particles are charged by varying the way of charging or the charging power with respect to time in such a manner that as a result of the charging, emitted particles brought into at least two different electrical charge states are present, wherein the charge of the emitted particles is further determined as a difference value/values measured from the emitted particles brought into said at least two different electrical charge states.

Abstract: The invention relates to the production of light-amplifying optical material. Liquid reactant is atomized into droplets using a high velocity gas. The droplets are subsequently introduced into a flame. Reactants are oxidized in the flame and condensed by forming small particles. At least a fraction of said particles is collected and fused to form optical waveguide material, which is subsequently drawn to form an optical waveguide. According to the invention, the velocity of the atomizing gas stream is in the order of the velocity of sound. The high velocity enhances atomization and increases reaction rates in the flame. The residence times are reduced to such a degree that unwanted phase transformations in the produced particles are substantially minimized. Consequently, very homogeneous material is produced. Especially, in the production of erbium-doped silica, low percentage of clustered erbium ions is achieved.

Abstract: The invention relates to a device (30) for determining the size distribution of aerosol particles from a flow (11), the device (30) comprising an electric mobility analyzer (10) and an impactor (20), connected to each other in such a way that the nozzle part (22a) of the first stage of the impactor (20) is simultaneously the bottom plate of said mobility analyzer (10).