CN106442238B - Device for detecting concentration of particles in air - Google Patents
Device for detecting concentration of particles in air Download PDFInfo
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- CN106442238B CN106442238B CN201610587160.XA CN201610587160A CN106442238B CN 106442238 B CN106442238 B CN 106442238B CN 201610587160 A CN201610587160 A CN 201610587160A CN 106442238 B CN106442238 B CN 106442238B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/0606—Investigating concentration of particle suspensions by collecting particles on a support
- G01N15/0612—Optical scan of the deposits
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
- G01N15/075—Investigating concentration of particle suspensions by optical means
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Abstract
The invention discloses a device for detecting the concentration of particles in air, which comprises a heating element (4), an air cavity (5) and a transparent mirror surface (6), wherein a thermophoresis effect exists between the heating element (4) and the transparent mirror surface (6), so that the particles in the air cavity (5) move towards the transparent mirror surface (6) and fall on the transparent mirror surface under the action of the thermophoresis effect; the device also comprises a light-emitting element (3), a data receiving unit (7), a data processing unit (8) and a display unit (9), wherein the light-emitting element (3) emits light to irradiate on the transparent mirror surface (6), a light spot is formed on the data receiving unit (7) by the light part through the transparent mirror surface (6), and the data processing unit (8) processes the light spot to obtain the concentration of particles in the air; the device has novel and simple structure, is easy for large-scale production and utilization, has smaller volume, is convenient to carry, is not limited by regions during measurement, and has accurate detection result.
Description
Technical Field
The invention relates to the field of air quality detection, in particular to detection of particle concentration in air, and specifically relates to a device for detecting particle concentration in air.
Background
In recent years, in many cities in China, dust haze weather appears, so that air is turbid, visibility is reduced, and the main reasons for forming dust haze weather are particulate pollutants in the atmosphere, wherein the main sources of the particulate pollutants are as follows: the compound discharged in the automobile exhaust, a large amount of dust released by fuel combustion, waste discharged in industrial production, various granular substances manufactured in industries such as building materials and the like. The particles in the atmosphere mainly comprise: TSP, PM 10 And PM 2.5 These particles, when inhaled into the human body, can be dangerous to human health.
Currently, the methods used to measure the concentration of fine particles in air are generally gravimetric, micro-oscillating balance, beta-ray and light scattering. Several methods have the advantages and disadvantages that the weight method is direct, but the operation is complicated and the equipment is heavy; the micro-oscillation balance method is reliable, but is not suitable for measuring the concentration of particles in a wet area; beta-ray method is not affected by particle size and composition of particles, but the measured value is generally higher; the light scattering method has small equipment volume, convenient carrying, but lower precision.
Disclosure of Invention
In order to overcome the problems, the inventor has conducted intensive studies and devised a novel device for detecting the concentration of particles in air, wherein the device is beneficial to depositing particles in air on a transparent mirror surface by thermophoresis effect under temperature gradient, then irradiating the mirror surface, and forming light spots after the light passes through the mirror surface due to the existence of the particles on the mirror surface, and the concentration of the particles in the air can be obtained according to the relation between the area of the light spots and the content of the particles, thereby completing the invention.
In one aspect, the present invention provides a device for detecting the concentration of particles in air, in particular in the following aspects:
(1) A device for detecting the concentration of particles in air, wherein the device comprises a shell 1, a heating element 4 and a transparent mirror surface 6 are arranged in the shell 1, and an air cavity 5 is arranged between the heating element 4 and the transparent mirror surface 6;
(2) The apparatus according to the above (1), wherein the housing 1 is made of a heat insulating material, which is glass fiber, asbestos, rock wool, foam or a vacuum insulation panel, preferably asbestos, foam or a vacuum insulation panel; preferably, a black aluminum foil is wrapped on the outer side of the heat insulating material for shielding the stray light outside the device, and the shell 1 is in a shape of a straight cylinder, such as a cylindrical straight cylinder, a square straight cylinder or a polygonal straight cylinder, preferably a cylindrical straight cylinder;
(3) The apparatus according to the above (1) or (2), wherein,
the heating element 4 is used for generating a temperature gradient in the air cavity 5, thereby giving thermophoresis force to particles in the air,
the transparent mirror 6 is used to carry particles deposited under thermophoretic forces,
preferably, the heating element 4 and the transparent mirror 6 respectively abut against the inner wall of the housing 1;
(4) The apparatus according to any one of the above (1) to (3), wherein,
the length-diameter ratio of the shell 1 is (3-8): (1-5), preferably (4-6): (2 to 4), more preferably 5:3, a step of; and/or
A heating element taking-out and placing-in valve 14 is arranged on the outer surface of the shell 1 and positioned on one side of the heating element 4 and is used for taking out or placing in the heating element 4; and/or
An air inlet and outlet valve 15 is arranged on the outer surface of the shell 1 and positioned on one side of the air cavity 5 for air inlet and outlet;
(5) The apparatus according to any one of the above (1) to (4), wherein,
the heating element 4 is a resistance flat plate; and/or
The surface of the transparent mirror surface 6 is a rough surface and/or transparent liquid glue is smeared on the surface of the transparent mirror surface 6, wherein the surface is one surface facing the heating element 4;
(6) The device according to one of the above (1) to (5), wherein a light emitting element 3 is provided on the side of the heat generating element 4 facing away from the air cavity 5, and optionally a power source 2 is provided, wherein,
the power supply 2 is used for providing electric energy for the light-emitting element 3; and/or
The light-emitting element 3 is used for emitting light and irradiating the light onto the transparent mirror surface 6 deposited with the particles, and the light passes through the transparent mirror surface 6 to form light spots;
(7) The device according to any one of the above (1) to (6), wherein the mirror surface of the light emitting element 3 employs a concave mirror for diffusing light so as to entirely cover the transparent mirror surface 6;
(8) The device according to any one of the above (1) to (7), wherein a data receiving unit 7, a data processing unit 8 and a display unit 9 are provided in this order in the light direction on the side of the transparent mirror 6 facing away from the air cavity 5,
the data receiving unit 7 is used for sensing the area of the light spot and converting the optical signal into an electric signal to be transmitted to the data processing unit 8;
the data processing unit 8 is used for processing the electric signals transmitted by the data receiving unit 7 to obtain the concentration of particles in the air;
(9) The apparatus according to any one of the above (1) to (8), wherein,
the data receiving unit 7 is a photosensitive device, preferably a photodiode, more preferably an avalanche photodiode; and/or
The data processing unit 8 is a data processor, preferably a high-pass cell 600 processor; and/or
The display unit 9 is a display.
In a further aspect the present invention provides the use of a device as described in any one of (1) to (9) above for detecting the concentration of particles in air.
Drawings
Fig. 1 shows a schematic structural diagram of an apparatus for detecting the concentration of particles in air according to the present invention.
Reference numerals illustrate:
1-shell
14-heating element taking and placing port valve
15-air inlet and outlet valve
2-power supply
3-light-emitting element
4-heating element
5-air cavity
6-transparent mirror
7-data receiving unit
8-data processing unit
9-display unit
Detailed Description
The invention is further described in detail below with reference to the accompanying drawings. The features and advantages of the present invention will become more apparent from the description.
Wherein, although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated.
The invention provides a device for detecting the concentration of particles in air, which comprises a shell 1, wherein a heating element 4 and a transparent mirror surface 6 are arranged in the shell 1, and an air cavity 5 is arranged between the heating element 4 and the transparent mirror surface 6; the air cavity 5 is used for placing or containing air with the concentration of particles to be detected; the heating element 4 can emit heat for generating thermophoresis force; the transparent mirror 6 is used to carry particles deposited under thermophoretic forces.
Wherein the heating element 4 emits heat, so that the temperature of the heating element 4 side is obviously higher than the temperature of the transparent mirror surface 6 side, and therefore, a temperature gradient is formed in the air cavity 5, a thermophoresis effect is generated, and particles in the air cavity 5 are given to thermophoresis force, namely, the particles move from a high temperature area to a low temperature area under the action of the thermophoresis effect (thermophoresis force), namely, the particles move from the heating element 4 to the transparent mirror surface 5 and finally fall on the transparent mirror surface 5.
In the present invention, the thermophoretic force refers to a force that particles move from a high temperature region to a low temperature region under the thermophoresis effect.
According to a preferred embodiment of the invention, the heating element 4 is a resistive plate.
In a further preferred embodiment, the resistor plate is self-charged, the battery is started, and the resistor starts to generate heat.
The reason why the heating element 4 is self-charged rather than connected to a power supply is to facilitate the later removal or placement of the heating element 4 from the device (after the end of particle deposition).
According to a preferred embodiment of the invention, the surface of the transparent mirror 6 is roughened, wherein the surface is the surface facing the heating element 4, i.e. the surface of the side for receiving the deposited particles in the air.
Wherein the surface is provided as a roughened surface for better adhesion of the particles to the transparent mirror.
According to another preferred embodiment of the invention, a transparent liquid glue is applied to the surface of the transparent mirror 6.
The coating amount of the liquid glue is not too much, and a thin layer is slightly covered, so that the purpose of selecting transparent liquid glue is to prevent light rays from penetrating through the transparent mirror surface and affecting the light spot area when the liquid glue is used for preventing later illumination. At the same time, the purpose of applying the liquid glue is also to better adhere the particles to the transparent mirror.
In the present invention, the rough surface may be simultaneously processed by treating the transparent mirror surface, and transparent liquid glue may be applied to the rough surface.
According to a preferred embodiment of the present invention, a heating element taking and placing port valve 14 is provided on the outer surface of the housing 1 at one side of the heating element 4.
The heating element taking and placing port valve 14 is used for conveniently taking the heating element out of the device after the particle deposition is finished, so that a later-stage illumination experiment can be performed.
According to a preferred embodiment of the invention, an air inlet and outlet valve 15 is provided on the outer surface of the housing 1 on the side of the air chamber 5.
The air inlet and outlet valve 15 is used for detecting air in the environment to be detected in the device. For example, if the concentration of particles in an environment is detected, the air inlet/outlet valve 15 of the device is opened, the device is placed in the environment, and air in the environment is introduced into the device for detection. Preferably, the heating element 4 is placed in the device before the air is placed in the device.
According to a preferred embodiment of the invention, the heating element 4 is provided with a light-emitting element 3 on the side facing away from the air cavity 5, optionally with a power supply 2; wherein the light-emitting element 3 is used for emitting light and irradiating the light onto the transparent mirror surface 6 deposited with particles; the power supply 2 is used for providing the light emitting element 3 with electrical energy.
The power supply may be optional, if the light emitting element 3 is powered by a battery, the power supply 3 is not needed, and if the light emitting element 3 is not powered by a battery, an external power supply is needed, that is, the power supply 2 is needed.
In the invention, the heating element 4 is firstly placed in the device, started to generate thermophoresis effect, so that particles are deposited on the transparent mirror surface 6, and then the mass of the particles is calculated, wherein the mass of the particles is deduced through the deposition area of the particles. In the invention, after all particles are deposited on the transparent mirror surface, the heating element 4 is taken out, the light-emitting element 3 is started to irradiate the transparent mirror surface 6, and light rays cannot penetrate through the mirror surface at the position with the particles on the mirror surface, but light rays at the position without the particles penetrate to form light spots, so that the light spot area has a direct relation with the quantity of the deposited particles, and the larger the concentration of the particles in the air, the more the deposited particles and the smaller the light spot area.
According to a preferred embodiment of the invention, the mirror surface of the light emitting element 3 is a concave mirror for diffusing the light to completely cover the transparent mirror surface 6.
According to a preferred embodiment of the invention, a data receiving unit 7, a data processing unit 8 and a display unit 9 are arranged in this order in the light direction on the side of the transparent mirror 6 facing away from the air space 5.
Wherein the data receiving unit is arranged at the adjacent side of the transparent mirror surface 6, light irradiates the transparent mirror surface 6 and irradiates the data receiving unit 7 through the transparent mirror surface 6, and the light cannot completely pass through the transparent mirror surface 6 due to the existence of particles on the transparent mirror surface 6, so that light spots are formed on the data receiving unit, and the data receiving unit 7 is used for sensing the areas of the light spots and converting optical signals into electric signals to be transmitted to the data processing unit 8; the data processing unit is used for processing the electric signal (namely the light spot area) transmitted by the data receiving unit 7, performing data processing to obtain the particle concentration, and transmitting the result to the display for displaying.
The deposition area of the particles on the transparent mirror surface is directly related to the area of the light spot, wherein the deposition area of the particles is equal to the area of the transparent mirror surface minus the area of the light spot, namely: s is S Particles ＝S Lens -S Light spot I.e. a larger spot area indicates fewer deposited particles, a lower concentration of particles in air and vice versa. Since the mass of the particles deposited by the particles has a certain functional relation with the spot area, the data processing unit 8 can obtain the mass m of the deposited particles according to the electric signal (spot area), and then divide the mass m by the volume of the air cavity 5 to obtain the mass concentration of the particles in the air.
It should be noted that the concentration of particles in the air is not particularly high, so that the particles in the air cavity are not deposited on the transparent lens in the detection process, and the phenomenon of repeated superposition of the particles is avoided.
According to a preferred embodiment of the present invention, the data receiving unit 7 is a photosensitive device.
In a further preferred embodiment, the data receiving unit 7 is a photodiode.
In a further preferred embodiment, the data receiving unit 7 is an avalanche photodiode.
The data receiving unit 7 should have photosensitivity, sense transmitted light, and have an ability to convert an optical signal into an electrical signal. The avalanche photodiode is a P-N junction type photodiode in which an avalanche multiplication effect of carriers is utilized to amplify a photoelectric signal to improve detection sensitivity.
According to a preferred embodiment of the invention, the data processing unit is a data processor.
In a further preferred embodiment, the data processing unit is a high-pass cell 600 processor.
According to a preferred embodiment of the invention, the display unit 9 is a display for displaying the detection result, i.e. the concentration of particles in the air, preferably the mass concentration.
In a further preferred embodiment, the display unit 9 is a liquid crystal display.
According to a preferred embodiment of the invention, the housing 1 is made of a thermally insulating material to ensure that the temperature inside the housing 1 remains unchanged, independent of the temperature of the environment outside the housing.
In a further preferred embodiment, the heat insulating material is glass fibre, asbestos, rock wool, foam or vacuum insulation panels, preferably asbestos, foam or vacuum insulation panels.
In a further preferred embodiment, a black aluminum foil is wrapped on the outside of the insulating material for shielding stray light outside the device.
Wherein, in order to guarantee that the inside thermophoresis effect of casing does not receive external environment temperature's influence, should guarantee the thermal insulation performance of casing, set up the purpose that black aluminium foil simultaneously is avoided external environment's light to the processing of the interior facula area of device to lead to the fact the influence.
According to a preferred embodiment of the invention, the housing 1 has a straight cylindrical shape.
In a further preferred embodiment, the housing 1 is a cylindrical cylinder, a square cylinder or a polygonal cylinder.
In a further preferred embodiment, the housing 1 is in the form of a cylindrical straight cylinder.
Among them, the purpose of providing the housing 1 in a straight cylindrical shape is as follows: firstly, the particles are ensured to move towards the transparent mirror surface 6 under thermophoresis force without being blocked; secondly, when the light-emitting element 3 irradiates, the emitted light can cover the transparent mirror surface 6. If this is not the case, the following phenomena occur: firstly, when the inner diameter of the shell 1 is firstly big and then small according to the temperature gradient direction (illumination direction), particles move under thermophoresis force, the movement space is gradually reduced, the movement is inevitably blocked, and even part of the particles possibly fall on a reduced wall and cannot fall on a transparent mirror surface, so that the detection is smaller than the actual value; secondly, when the inner diameter of the shell 1 is small and then large according to the temperature gradient direction (illumination direction), the space in the shell is small and then large, and the light rays start from the smaller end, so that no light rays can be transmitted around the larger end, but particles can be deposited around the larger end, and therefore the final structure is influenced, and the detection is smaller than the actual value. Therefore, it is necessary to provide the housing 1 in a straight cylindrical shape so that the particle deposition process and the light transmission process are not hindered.
According to a preferred embodiment of the invention, the edges of the heating element 4, the transparent mirror 6, the data receiving unit 7 each bear against the inner wall of the housing 1, i.e. they are all of the same size as the housing interior.
Wherein the purpose of the heating element 4 and the transparent mirror 6 being of the same size as the interior of the housing is to ensure that particles after entering the air cavity 5 do not flow to other areas, but are accurately blocked in the air cavity 5 between the heating element 4 and the transparent mirror 6; the reason why the data receiving unit 7 is also the same size as the inside of the housing is that it needs to be exactly the same size as the transparent mirror 6 to receive all the light spots, ensuring that the light spot area is accurate, whereas the transparent mirror 6 is the same size as the inside of the housing, and therefore the data receiving unit 7 is also the same size as the inside of the housing.
According to a preferred embodiment of the invention, the aspect ratio of the shell is (3-8): (1-5), preferably (4-6): (2 to 4), more preferably 5:3.
if the length-diameter ratio of the shell is too small, the distance from the heating element to the transparent mirror surface is too short, the temperature of the heating element can also slowly influence the temperature of the transparent mirror surface, so that the temperature of the whole air cavity is increased, the temperature difference is small, and the thermophoresis effect is not obvious. If the aspect ratio of the shell is too large, the thermophoresis effect cannot reach the transparent mirror, i.e., the particles are difficult to flow to the transparent mirror, or the time required for thermophoresis precipitation is too long, so that a reasonable aspect ratio is required.
The invention also provides a method for detecting the concentration of particles in the air by using the device, which is carried out as follows:
and 3, performing data processing through a data processing unit 8, and transmitting the processing result to a display unit 9 for display to obtain the concentration of particles in the air.
According to a preferred embodiment of the invention, said step 1 comprises the following sub-steps:
step 1-1, placing the heating element 4 into the device, and closing a heating element taking and placing port valve 14;
step 1-2, opening an air inlet and outlet valve 15 to enable air to be tested to be filled in the air cavity 5, and then closing the air inlet and outlet valve 15;
and step 1-3, starting the heating element 4 to generate a thermophoresis effect so as to deposit particles on the transparent mirror surface 6.
According to a preferred embodiment of the present invention, after step 1, before step 2, the heating element 4 is removed and the heating element removal port valve 14 is closed.
Wherein the heating element 4 needs to be taken out before illumination, otherwise the heating element 4 withstands the light emitted by the light emitting element 3.
According to a preferred embodiment of the invention, step 3 comprises the sub-steps of:
step 3-1, the data processing unit 8 receives the electric signals transmitted by the data receiving unit 7, and the electric signals are processed to obtain the light spot area;
step 3-2, obtaining particle quality according to a functional relation between the light spot area and the particle quality;
and 3-3, dividing the particle mass by the volume of the air cavity 5 to obtain the concentration of the particles in the air.
In the invention, a certain relation exists between the light spot area and the particle mass, and the larger the light spot area is, the more the particle mass is, the smaller the light spot area is, and the less the particle mass is. The specific functional relation between the two can be obtained through experimental verification: the experiment is carried out according to the steps 1-3, the light spot area is obtained, then the transparent mirror surface 6 is taken out, the particle mass on the transparent mirror surface is weighed (preferably, a layer of transparent plastic film is arranged on the transparent mirror surface, the film and deposited particles are weighed together, then the weight of the film is subtracted, namely the weight of the particles is obtained), then the particle mass corresponding to the light spot area is respectively obtained, the experiment is repeated to obtain a series of data of the light spot area and the particle mass, and then fitting is carried out, so that the function relation between the light spot area and the particle mass is obtained. The functional relationship is imported into a data processing unit, and can be directly applied in practical application.
The invention has the beneficial effects that:
(1) The device provided by the invention has novel and simple structure and is suitable for large-scale production and application;
(2) The device provided by the invention can detect the concentration of small particles with the particle size smaller than 2.5 mu m in the air;
(3) The device provided by the invention has the advantages of small volume, portability, no regional limitation during measurement and accurate detection result.
In the description of the present invention, it should be noted that the positional or positional relationship indicated by the terms "upper", "inner" and "outer", etc. are based on the positional or positional relationship in the operation state of the present invention, are merely for convenience of describing the present invention and simplifying the description, and are not indicative or implying that the apparatus or element in question must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.
The invention has been described above in connection with preferred embodiments, which are, however, exemplary only and for illustrative purposes. On this basis, the invention can be subjected to various substitutions and improvements, and all fall within the protection scope of the invention.
Claims (10)
1. A device for detecting the concentration of particles in air, which is characterized by comprising a shell (1), wherein a heating element (4) and a transparent mirror surface (6) are arranged in the shell (1), and an air cavity (5) is arranged between the heating element (4) and the transparent mirror surface (6);
the heating element (4) is used for generating a temperature gradient in the air cavity (5) so as to endow particles in the air with thermophoresis force;
the transparent mirror (6) is used for bearing particles deposited under the action of thermophoresis force;
the heating element (4) and the transparent mirror surface (6) are respectively propped against the inner wall of the shell (1);
a light-emitting element (3) and a power supply (2) are arranged on one side of the heating element (4) which is away from the air cavity (5),
the power supply (2) is used for providing electric energy for the light-emitting element (3);
the light-emitting element (3) is used for emitting light and irradiating the light on the transparent mirror surface (6) deposited with the particles, and the light passes through the transparent mirror surface (6) to form light spots;
a data receiving unit (7), a data processing unit (8) and a display unit (9) are sequentially arranged on one side of the transparent mirror surface (6) which is away from the air cavity (5) along the light direction,
the data receiving unit (7) is used for sensing the area of the light spot and converting the optical signal into an electric signal to be transmitted to the data processing unit (8);
the data processing unit (8) is used for processing the electric signals transmitted by the data receiving unit (7) to obtain the concentration of particles in the air.
2. The device according to claim 1, characterized in that the housing (1) is made of a heat insulating material, which is fiberglass, asbestos, rock wool, foam or vacuum insulation panels;
and the outer side of the heat insulating material is wrapped with black aluminum foil for shielding stray light outside the device, and the shell (1) is in a straight cylinder shape.
3. The apparatus of claim 2, wherein the device comprises a plurality of sensors,
the heat insulating material is asbestos, foamed plastic or a vacuum heat insulating board;
the shell (1) is a cylindrical straight cylinder, a square straight cylinder or a polygonal straight cylinder.
4. The apparatus of claim 1, wherein the device comprises a plurality of sensors,
the length-diameter ratio of the shell (1) is (3-8) (1-5); and/or
A heating element taking-out and placing-in opening valve (14) is arranged on the outer surface of the shell (1) and positioned on one side of the heating element (4) and is used for taking out or placing in the heating element (4); and/or
The air cavity (5) is used for placing air with the concentration of particles to be detected.
5. The apparatus of claim 4, wherein the device comprises a plurality of sensors,
the length-diameter ratio of the shell (1) is (4-6): (2-4); and/or
An air inlet and outlet valve (15) is arranged on the outer surface of the shell (1) and positioned on one side of the air cavity (5) for air to enter and exit.
6. The apparatus of claim 1, wherein the device comprises a plurality of sensors,
the heating element (4) is a resistance flat plate; and/or
The surface of the transparent mirror surface (6) is a rough surface and/or,
and (3) coating transparent liquid glue on the surface of the transparent mirror surface (6), wherein the surface is one surface facing the heating element (4).
7. The device according to one of claims 1 to 6, characterized in that the mirror surface of the light-emitting element (3) is a concave mirror for diverging the light rays to completely cover the transparent mirror surface (6).
8. The device according to any one of claims 1 to 6, wherein,
the data receiving unit (7) is a photosensitive device; and/or
The data processing unit (8) is a data processor; and/or
The display unit (9) is a display.
9. The apparatus of claim 8, wherein the device comprises a plurality of sensors,
the data receiving unit (7) is an avalanche photodiode; and/or
The data processing unit (8) is a high-pass cell 600 processor.
10. Use of a device according to one of claims 1 to 9 for detecting the concentration of particles in air.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2007323301A1 (en) * | 2006-11-20 | 2008-05-29 | Nanotemper Technologies Gmbh | Fast thermo-optical particle characterisation |
| DE102010027849A1 (en) * | 2010-04-16 | 2011-10-20 | Robert Bosch Gmbh | Particle concentration determining arrangement for exhaust gas of combustion engine of motor car, has signal processing unit determining correction factor for output signal of measurement unit, where output signal contains dilution factors |
| CN103411864A (en) * | 2013-08-05 | 2013-11-27 | 深迪半导体(上海)有限公司 | MEMS sensor for measuring gas suspended particle concentration based on structural resonance |
| CN205157382U (en) * | 2015-10-29 | 2016-04-13 | 上海基恩自动化设备有限公司 | Particulate matter concentration measurement appearance |
| CN206057141U (en) * | 2016-07-22 | 2017-03-29 | 华北电力大学 | A kind of device of detection air middle particle concentration |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2002365247B2 (en) * | 2001-08-03 | 2006-06-08 | Nanosphere, Inc. | Nanoparticle imaging system and method |
| US7168292B2 (en) * | 2003-05-15 | 2007-01-30 | The Regents Of The University Of California | Apparatus for particulate matter analysis |
| US8941080B2 (en) * | 2008-05-20 | 2015-01-27 | Ludwig-Maximilians-Universitat Munchen | Method and device for particle analysis using thermophoresis |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2007323301A1 (en) * | 2006-11-20 | 2008-05-29 | Nanotemper Technologies Gmbh | Fast thermo-optical particle characterisation |
| DE102010027849A1 (en) * | 2010-04-16 | 2011-10-20 | Robert Bosch Gmbh | Particle concentration determining arrangement for exhaust gas of combustion engine of motor car, has signal processing unit determining correction factor for output signal of measurement unit, where output signal contains dilution factors |
| CN103411864A (en) * | 2013-08-05 | 2013-11-27 | 深迪半导体(上海)有限公司 | MEMS sensor for measuring gas suspended particle concentration based on structural resonance |
| CN205157382U (en) * | 2015-10-29 | 2016-04-13 | 上海基恩自动化设备有限公司 | Particulate matter concentration measurement appearance |
| CN206057141U (en) * | 2016-07-22 | 2017-03-29 | 华北电力大学 | A kind of device of detection air middle particle concentration |
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