The system, configured for being on board an aircraft, includes a probe for collecting samples of contrail, a chamber for collecting the samples, a collecting conduit for conducting the samples from the collecting probe the collecting chamber and at least one device for measuring at least one parameter characterizing the samples in the collecting conduit while they are conducted from the collecting probe to the collecting chamber. By virtue of the system, it is not necessary to use a second aircraft that follows the aircraft for collecting samples of contrail.

The sensor includes: a collection part 30L, 30M, 30S in which, a plurality of filter members for collecting particulate matter in exhaust gas are arranged in descending order of porosity from an exhaust upstream side to an exhaust downstream side of the exhaust gas; a pair of electrodes 32, 33 which is arranged to each of the plurality of filter members 30L, 30M, 30S and facing each other with the plurality of filter members interposed therebetween; and estimation means 42 to 44 far estimating a particulate matter amount collected on each of the plurality of filter members having different porosities based on a capacitance change amount between the pair of electrodes 32, 33.

The aerosol diluting apparatus includes a first diluting unit to provide a first modified sample flow by combining an aerosol sample flow with a first diluting gas flow, an ejector unit to draw the first modified sample flow from the first diluting unit to the ejector unit and to provide a second modified sample flow by mixing a second dilution gas flow with the first modified sample flow, a control unit, and a control valve, wherein the control unit and the control valve are arranged to adjust flow rate of the second dilution gas flow according to an inlet pressure of the aerosol sample flow, so as to keep the dilution factor of the diluting apparatus substantially independent of the inlet pressure.

The present invention relates to a method for measuring condensable particulate matters formed from exhaust gas of an internal combustion engine, including the steps of sucking exhaust gas from the internal combustion engine; diluting the sucked exhaust gas to simulate it to atmospheric condition; a first measurement step of branching some of the exhaust gas of the atmospheric condition and measuring particulate matters including condensable particulate matters and filterable particulate matters; a second measurement step of branching the rest of the exhaust gas of the atmospheric condition to remove the condensable particulate matters and measuring the particulate matters including only the filterable particulate matters; and comparing the first measurement step and the second measurement step to calculate an amount of the condensable particulate matters in the exhaust gas of the atmospheric condition.

A semi-volatile particulate matter detection device is disclosed for detecting semi-volatile particulate matter in a gas flow. The device has a first filter stage for receiving the gas flow, the first filter stage being configured to capture particulate matter and to be heated to a temperature of at least 150° C. to volatilise semi-volatile particulate matter to produce semi-volatile vapour for passing through the first filter stage with the gas flow. The device also has a conveyance section downstream of the first filter stage to convey the gas flow and the semi-volatile vapour. A second filter stage is configured to receive the flow from the conveyance section. The temperature of the conveyance section and/or of the second filter stage is controllable so as to cause condensation of at least some of the semi-volatile vapour and collect it on the second filter stage. A detector is provided for detecting at least one characteristic of the condensed semi-volatile vapour on the second filter stage.

To provide an exhaust gas analysis apparatus that, without the need to greatly change the flow rate of diluted exhaust gas passing through a filter, can change the flow rate of exhaust gas in the diluted exhaust gas passing through the filter with good followability to reflect weighting, and accurately measure PM, the exhaust gas analysis apparatus is adapted to include: a collection part that collects particulate matter in sampling exhaust gas partially splitting from original exhaust gas or in the diluted exhaust gas resulting from diluting the sampling exhaust gas with diluent gas; and a split flow ratio control mechanism configured to, in accordance with a vehicle driving mode set in compliance with predetermined regulations, change a split flow ratio that is the ratio of the split flow rate of the sampling exhaust gas to the total flow rate of the original exhaust gas.

The invention relates to a photometer (30) for analysing the composition of a sample gas. The photometer comprises an infra-red (IR) source (20) configured to direct a first plurality of pulses (40) of IR radiation through the sample gas to an IR detector (26), at least two of the first plurality of pulses being of different wavelength. The photometer further comprises an ultraviolet (UV) source (32) configured to generate a second plurality of pulses (38) of UV radiation for conveyance to a UV detector (36), at least two of the second plurality of pulses being of different wavelength. A path selection arrangement (22, 42-50) is configured to selectively convey different ones of the second plurality of pulses (38) to one of the sample gas and the UV detector (36). The photometer further comprises processing circuitry coupled to the IR source (20), the UV source (32), the IR detector (26), the UV detector (36) and the path selection arrangement (22, 42-50). The processing circuitry is configured to (i) select the wavelength to be used for a given UV pulse of the second plurality of pulses (38), (ii) receive a plurality of detection signals from each of the IR detector (26) and the UV detector (36) and (iii) based on the detection signals, determine a concentration of at least one component of the sample gas. A method for analysing the composition of a sample gas is also disclosed.

An apparatus for measuring aerosol particles includes a charging unit to form charged particles by charging particles of an aerosol sample flow by diffusion charging, and a collecting unit to provide an electric current by collecting charges from the charged particles by diffusion of the charged particles, the electric current being indicative of number density of aerosol particles of the aerosol sample flow.

The internal pressure of the collecting unit is maintained at a reduced value in order to provide a flat response of the electric current for detecting nanoparticles of different sizes.

A particle sensor is described. The particle sensor includes a laser module having a laser, and a detector configured to detect thermal radiation. The particle sensor has an optical apparatus that is configured to focus laser light proceeding from the laser module into a first spot and is configured to focus thermal radiation proceeding from the first spot into a second spot, a radiation-sensitive surface of the detector being located in the second spot, or behind the second spot in the beam path of the thermal radiation focused onto the second spot.

A dilution gas mixing unit that is used in an exhaust gas analysis system that analyzes the mixed gas obtained by diluting an exhaust gas with the dilution gas, and mixes the dilution gas with the exhaust gas is provided with a dilution gas supply pipe that is connected to an exhaust gas introduction pipe into which the exhaust gas is introduced and supplies the dilution gas to the exhaust gas introduction pipe, a dilution gas sampling unit that is provided in the dilution gas supply pipe and collects the dilution gas, and a backflow prevention member that is provided closer to the exhaust gas introduction pipe than the dilution gas sampling unit in the dilution gas supply pipe and prevents the mixed gas from flowing backward through the dilution gas supply pipe.