US3806248A - Continuous flow condensation nuclei counter - Google Patents

Continuous flow condensation nuclei counter Download PDF

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US3806248A
US3806248A US00334497A US33449773A US3806248A US 3806248 A US3806248 A US 3806248A US 00334497 A US00334497 A US 00334497A US 33449773 A US33449773 A US 33449773A US 3806248 A US3806248 A US 3806248A
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counter
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D Sinclair
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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
    • G01N15/065—Investigating concentration of particle suspensions using condensation nuclei counters

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  • ABSTRACT A condensation nuclei particle counter for continuous operation capable of condensing out nuclei within the range of1O.002-O.I micrometers;
  • the aerosol is humidified by a pool of an alcohol or other volatile liquid of low freezing point and then condensed in a chamber whose walls are maintained at a temperature of 10 to 20 C.
  • a light beam is passed through the resultant fog and the attenuation is measured as an indication of the particle density.
  • a preferred embodiment of thisinvention consists of a chamber wherein the aerosol of interest is mixed with l a suitable condensablevapor such as an alcohol, and another chamber maintained at a substantially lower temperature into which the mixture passes for cooling to supersaturation and formation of a fog.
  • substantially lower temperature is meant.
  • the chambers are provided with turbulence producing baffles and a detection system for measuringthe visible concentration of the fog.
  • the detection system may consist of a light source atan end of the. cold chamber and a light detection and measuringdevice such as a photo'cellat the other end to sense thelight attenuation caused by the fog.
  • the apparatus is continuously. operating, that is, fresh aerosol is continuously drawn in andexhausted.
  • the'nuclei counter would be used in conjunction-with an aerosol measuring system such as a. diffusion battery to measure particle size and size distribution.
  • It is thus a principal object of this invention to provide a continuous flow particle counter for determining nuclei concentration and size in the sub-microscopic particle size range.
  • FIGURE illustrates an elevation view in section of a preferred embodiment of this invention
  • counter 10 consists of an elongated housing l2 which may be rectangular or circular in cross section surrounded by a layer of thermal insulation 14.
  • a cylindrical container 16 is mounted above housingv 12 with an access tube 18 providing communication as illustrated between end chambers within these two members.
  • Container 16' is divided into several chambers by baffles 22a, 22b and 22c each of which is provided with an axial opening'24a, 24b and 240, respectively.
  • baffles 22a, 22b and 22c each of which is provided with an axial opening'24a, 24b and 240, respectively.
  • a liquid pool 25 is provided in all of the chambers, except, of course, the end chamber having access tube 18.
  • the liquid making up pool 25 is any liquid which will evaporate under the conditions described and condense when cooled to form a fog.
  • baffles 220 and 22b are provided with small openings 27a and 27b, respectively, to provide a uniform level of said pool. Liquid is inserted through a small opening 25a which may be closed with a stopper 25b. There is provided an aerosol inlet tube 26 to a chamber of container 16 at. the upstream or opposite end of the latter from access tube 18.
  • Container 12 is divided into chambers by baffles 28a-28e having openings as illustrated.
  • the bottoms of baffles 28a-28e are provided with small openings 29a-29e, respectively, to permit drainage of condensed vapor.
  • An exhaust tube 32 to carry away the as already described.
  • Flow of the aerosol is indicated by arrows
  • Extending from the downstream end of housing 12 is an assembly 34' containing an electric lamp 36 and a lens 38 mounted on a sleeve 39 with O-rings40 and 41. When lamp 36is energized, light is directed by lens 38 down through the length of housing 12, passing through the central openings in baffles 28a-28'e.
  • a photocell and window assembly 42 which comprises a sleeve 44 with O-rings 46 and 48, baffle 28a, and photocell unit 52.
  • the latter measures the light received from lamp 36, and'as is understood in the art, suitable apparatus (not shown) is provided to record and/or indicate the intensity of the light received by photocell unit 52.
  • the aerosol mixes with thevapors of the liquid making up pool 25, baffles 24a24c acting to promote turbulence thereby increasing the extent to which the mixing takes place and forming a near saturated mixture.
  • the gaseous mixture passes into housing 12 by way of access tube 18 and flows the length of housing 12 at the downstream end of which the mixture leaves by way of exhaust tube 32.
  • Baffles 28a28e similarly promote turbulence and thorough mixing within the chambers.
  • the walls of housing 12 are maintained at a suitable lower temperature such that the gaseous mixture is cooled sufficiently to become super-saturated, a fog being formed due to the presence of the nuclei in theaerosol.
  • the turbulence caused by baffles 28a-28e enhances heat transfer between the walls of housing 12 and the gaseous mixture, insuring an adequate low temperature throughout the gaseous fluid.
  • the resulting fog attenuates the light passing from lamp 36 to photocell unit 52 and the observed or recorded intensity of the light is a direct indication of the number of particles within the aerosol.
  • Counter 10 is calibrated by running aerosols of known particulate content through the apparatus.
  • An important aspect of this invention involves the maintenance of sufficiently high saturation under dynamic conditions in contrast to the static conditions found in other such devices during humidification and temperature equalization of the sample. This effect is enhanced in the present invention by utilizing as the liquid in pool 25 an alcohol, preferably ethanol, and maintaining the temperature of the walls of housing 12 in the range of about -l0C. to -C.
  • an alcohol preferably ethanol
  • EXAMPLE A counter was constructed with container 16 made from a copper tube 30.5 cm long and 5.1 cm diameter containing a 1 cm deep pool of ethyl alcohol. Housing 4 --10C. to --20C. temperature range. This counter was able to produce a fog out of nuclei down to about 0.002 micrometers diameter.
  • An important feature of this invention is that it pro-' a. means forming a first chamber for mixing therein said aerosol with a condensable vapor, said chamber containing a pool of the aforesaid condensed vapor, said mixing taking place above said pool;
  • b. means forming a second chamber whose walls are maintained at a temperature substantially lower than the temperature within said first chamber;
  • c. means for continuously delivering a mixture of said aerosol and vapor from said first chamber into said second chamber where a visible fog is formed from said mixture due to the cooling effect on the walls of said second chamber;
  • e. means-for continuously detecting the visible nuclei concentration of said fog.
  • the counter of claim 1 having means for maintaining turbulent flow conditions within said chambers.
  • said detecting means comprises a light source and means for measuring lightfrom said light source after passing through said second chamber, whereby the fog within said second chamber attenuates the light passing through.

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Abstract

A condensation nuclei particle counter for continuous operation capable of condensing out nuclei within the range of 0.002-0.1 micrometers. The aerosol is humidified by a pool of an alcohol or other volatile liquid of low freezing point and then condensed in a chamber whose walls are maintained at a temperature of -10* to -20* C. A light beam is passed through the resultant fog and the attenuation is measured as an indication of the particle density.

Description

United States Patent 1191 Sinclair 1111 3,806,248 1451 Apr. 23, 1974 CONTINUOUS FLOW CONDENSATION NUCLEI COUNTER Inventor: David Sinclair, Martinsville, NJ.
Assignee: The United States of America as represented by theUnited States Atomic Energy Commission, Washington, D.C.
Filed: Feb. 21, 1973 Appl. No.: 334,497
us. (:1. 356/37 Int. Cl. @0111 1/00 Field of Search 356/37, 102, 103; 340/236 [56] References Cited UNITED STATES PATENTS 3,592,546 7/1971 Gussman 356/37 Primary Examiner-Ronald L. Wibert Assistant Examiner-V. P. McGraw Attorney, Agent, or Firm-John A. l-loran; Leonard Belkin [57] ABSTRACT A condensation nuclei particle counter for continuous operation capable of condensing out nuclei within the range of1O.002-O.I micrometers; The aerosol is humidified by a pool of an alcohol or other volatile liquid of low freezing point and then condensed in a chamber whose walls are maintained at a temperature of 10 to 20 C. A light beam is passed through the resultant fog and the attenuation is measured as an indication of the particle density.
5 Claims, 1 "Dravving Figure 9/1972 Rich 356/37 I CONTINUOUS FLOW CONDENSATION NUCLEI COUNTER BACKGROUND OF THE INVENTION osols such as cloud, fog, smog, dust, and haze in which I there is a great deal of concern. The size range of particular interest for'the condensation nuclei is 0.002 to 0.1 micrometers.
Conventional apparatus such as light-scattering pho-v tometers and light microscopes are not capable of measuring particulates of such small size. Furthermore, techniques which can be employed in the measurement of such small particles do not conveniently lend themselves to continuous on-line operation and are generally too inconvenient and too complicated to employ on a regular basis for monitoring atmospheric conditions. Continuously operating devices which have been developed lack sufficient portability which would permit on short notice the measurement of aerosol conditions at different locations. Furthermore, a continuous operating device which has been developed requires the use of a secondary flow of cold air to bring the temperature of the aerosol down to proper supersaturating conditions and it has been found that such an arrangement will not measure particles present down to. 0.002 micrometers diameter.
SUMMARY OF THE PRESENT INVENTION Many of the aforementioned problems are overcome by the present invention in which it is possible to measure aerosols in the sub-micron range of 0.002 to 0.1 micrometers on a continuous basis, with little difficulty and inconvenience, and with great accuracy. An additional feature of this invention is that the 'apparatus is such that it can be moved to different locations quickly and with a minimum of inconvenience. Briefly described, a preferred embodiment of thisinvention consists of a chamber wherein the aerosol of interest is mixed with l a suitable condensablevapor such as an alcohol, and another chamber maintained at a substantially lower temperature into which the mixture passes for cooling to supersaturation and formation of a fog. By substantially lower temperature is meant. a temperature low enough to cause the fog to form aboutthe nuclei. The chambers are provided with turbulence producing baffles and a detection system for measuringthe visible concentration of the fog. The detection system may consist of a light source atan end of the. cold chamber and a light detection and measuringdevice such as a photo'cellat the other end to sense thelight attenuation caused by the fog. The apparatusis continuously. operating, that is, fresh aerosol is continuously drawn in andexhausted. Typically, the'nuclei counter would be used in conjunction-with an aerosol measuring system such as a. diffusion battery to measure particle size and size distribution.
It" is thus a principal object of this invention to provide a continuous flow particle counter for determining nuclei concentration and size in the sub-microscopic particle size range.
Other objects and advantages of this invention will hereinafter become evident from the following description of a preferred embodiment of this invention.
BRIEF DESCRIPTION OF THE DRAWING The FIGURE illustrates an elevation view in section of a preferred embodiment of this invention,
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the FIGURE, counter 10 consists of an elongated housing l2 which may be rectangular or circular in cross section surrounded by a layer of thermal insulation 14. A cylindrical container 16 is mounted above housingv 12 with an access tube 18 providing communication as illustrated between end chambers within these two members. Container 16' is divided into several chambers by baffles 22a, 22b and 22c each of which is provided with an axial opening'24a, 24b and 240, respectively. For reasons which will be apparent later, a liquid pool 25 is provided in all of the chambers, except, of course, the end chamber having access tube 18. The liquid making up pool 25 is any liquid which will evaporate under the conditions described and condense when cooled to form a fog. The bottoms of baffles 220 and 22b are provided with small openings 27a and 27b, respectively, to provide a uniform level of said pool. Liquid is inserted through a small opening 25a which may be closed with a stopper 25b. There is provided an aerosol inlet tube 26 to a chamber of container 16 at. the upstream or opposite end of the latter from access tube 18.
' Container 12 is divided into chambers by baffles 28a-28e having openings as illustrated. The bottoms of baffles 28a-28e are provided with small openings 29a-29e, respectively, to permit drainage of condensed vapor. An exhaust tube 32, to carry away the as already described. Flow of the aerosol is indicated by arrows Extending from the downstream end of housing 12 is an assembly 34' containing an electric lamp 36 and a lens 38 mounted on a sleeve 39 with O-rings40 and 41. When lamp 36is energized, light is directed by lens 38 down through the length of housing 12, passing through the central openings in baffles 28a-28'e.
At the upstream end of container 12 is a photocell and window assembly 42 which comprises a sleeve 44 with O- rings 46 and 48, baffle 28a, and photocell unit 52. The latter measures the light received from lamp 36, and'as is understood in the art, suitable apparatus (not shown) is provided to record and/or indicate the intensity of the light received by photocell unit 52.
The aerosol mixes with thevapors of the liquid making up pool 25, baffles 24a24c acting to promote turbulence thereby increasing the extent to which the mixing takes place and forming a near saturated mixture. At thedownstream end of container 16 the gaseous mixture passes into housing 12 by way of access tube 18 and flows the length of housing 12 at the downstream end of which the mixture leaves by way of exhaust tube 32. Baffles 28a28e similarly promote turbulence and thorough mixing within the chambers. The walls of housing 12 are maintained at a suitable lower temperature such that the gaseous mixture is cooled sufficiently to become super-saturated, a fog being formed due to the presence of the nuclei in theaerosol. The turbulence caused by baffles 28a-28e enhances heat transfer between the walls of housing 12 and the gaseous mixture, insuring an adequate low temperature throughout the gaseous fluid.
The resulting fog attenuates the light passing from lamp 36 to photocell unit 52 and the observed or recorded intensity of the light is a direct indication of the number of particles within the aerosol.
Counter 10 is calibrated by running aerosols of known particulate content through the apparatus.
An important aspect of this invention involves the maintenance of sufficiently high saturation under dynamic conditions in contrast to the static conditions found in other such devices during humidification and temperature equalization of the sample. This effect is enhanced in the present invention by utilizing as the liquid in pool 25 an alcohol, preferably ethanol, and maintaining the temperature of the walls of housing 12 in the range of about -l0C. to -C.
EXAMPLE A counter was constructed with container 16 made from a copper tube 30.5 cm long and 5.1 cm diameter containing a 1 cm deep pool of ethyl alcohol. Housing 4 --10C. to --20C. temperature range. This counter was able to produce a fog out of nuclei down to about 0.002 micrometers diameter.
An important feature of this invention is that it pro-' a. means forming a first chamber for mixing therein said aerosol with a condensable vapor, said chamber containing a pool of the aforesaid condensed vapor, said mixing taking place above said pool;
b. means forming a second chamber whose walls are maintained at a temperature substantially lower than the temperature within said first chamber;
c. means for continuously delivering a mixture of said aerosol and vapor from said first chamber into said second chamber where a visible fog is formed from said mixture due to the cooling effect on the walls of said second chamber;
d. means for continuously withdrawing mixture from said second chamber; and
e. means-for continuously detecting the visible nuclei concentration of said fog.
2. The counter of claim 1 having means for maintaining turbulent flow conditions within said chambers.
3. The counter of claim 2 in which said condensable vapor is an alcohol.
4. The counter of claim'3 in which the walls of said second chamber are maintained at a temperature of -10 to 20C.
5. The counter of claim 2 in which said detecting means comprises a light source and means for measuring lightfrom said light source after passing through said second chamber, whereby the fog within said second chamber attenuates the light passing through.

Claims (5)

1. A continuous flow particle counter for determining the nuclei concentration of an aerosol comprising: a. means forming a first chamber for mixing therein said aerosol with a condensable vapor, said chamber containing a pool of the aforesaid condensed vapor, said mixing taking place above said pool; b. means forming a second chamber whose walls are maintained at a temperature substantially lower than the temperature within said first chamber; c. means for continuously delivering a mixture of said aerosol and vapor from said first chamber into said second chamber where a visible fog is formed from said mixture due to the cooling effect on the walls of said second chamber; d. means for continuously withdrawing mixture from said second chamber; and e. means for continuously detecting the visible nuclei concentration of said fog.
2. The counter of claim 1 having means for maintaining turbulent flow conditions within said chambers.
3. The counter of claim 2 in which said condensable vapor is an alcohol.
4. The counter of claim 3 in which the walls of said second chamber are maintained at a temperature of -10* to -20*C.
5. The counter of claim 2 in which said detecting means comprises a light source and means for measuring light from said light source after passing through said second chamber, whereby the fog within said second chamber attenuates the light passing through.
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Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3512854A1 (en) * 1984-04-12 1985-10-17 United States Department Of Energy, Washington, D.C. DEVICE AND METHOD FOR SAMPLING SUBMICRON PARTICLES
US4790650A (en) * 1987-04-17 1988-12-13 Tsi Incorporated Condensation nucleus counter
WO1989008245A1 (en) * 1988-03-02 1989-09-08 Pacific Scientific Company Device for enlarging aerosol particles by coating them with liquid
US4950073A (en) * 1989-02-10 1990-08-21 Pacific Scientific Company Submicron particle counting enlarging the particles in a condensation based growth process
EP0416472A2 (en) * 1989-09-06 1991-03-13 Air Products And Chemicals, Inc. Process for sizing particles using condensation nucleus counting
US5118959A (en) * 1991-05-03 1992-06-02 Tsi Incorporated Water separation system for condensation particle counter
US5578995A (en) * 1994-01-25 1996-11-26 Chemtrac Systems, Inc. Method of monitoring and controlling condensate quality
US5659388A (en) * 1996-09-11 1997-08-19 Vlsi Standards, Inc. Method and apparatus for operating a condensation nucleus counter with improved counting stability and accuracy over a variable detection threshold
US5903338A (en) * 1998-02-11 1999-05-11 Particle Measuring Systems, Inc. Condensation nucleus counter using mixing and cooling
US6125845A (en) * 1997-08-29 2000-10-03 Tsi Incorporated Respirator fit-testing with size selected aerosol
WO2001027589A1 (en) * 1999-10-12 2001-04-19 California Institute Of Technology Fast mixing condensation nucleus counter
US6469780B1 (en) 1998-12-21 2002-10-22 Air Products And Chemicals, Inc. Apparatus and method for detecting particles in reactive and toxic gases
US6639671B1 (en) 2002-03-01 2003-10-28 Msp Corporation Wide-range particle counter
US20030202169A1 (en) * 2002-04-24 2003-10-30 Liu Benjamin Y.H. Compact, high-efficiency condensation nucleus counter
US6712881B2 (en) 2002-01-30 2004-03-30 Aerosol Dynamics Inc. Continuous, laminar flow water-based particle condensation device and method
US20060048783A1 (en) * 2004-09-09 2006-03-09 Msp Corporation Personal mask test system
US20070242261A1 (en) * 2005-08-25 2007-10-18 Msp Corporation Aerosol measurement by dilution and particle counting
US20080083274A1 (en) * 2006-10-10 2008-04-10 Hering Susanne V High saturation ratio water condensation device and method
US20080152547A1 (en) * 2006-12-22 2008-06-26 Thermo Electron Corporation Devices, methods, and systems for detecting particles in aerosol gas streams
US8192523B1 (en) 2008-02-22 2012-06-05 Tsi Incorporated Device and method for separating and increasing the concentration of charged particles in a sampled aerosol
US8305582B2 (en) 2009-09-01 2012-11-06 Alltech Associates, Inc. Methods and apparatus for analyzing samples and collecting sample fractions
US8305581B2 (en) 2007-12-05 2012-11-06 Alltech Associates, Inc. Methods and apparatus for analyzing samples and collecting sample fractions
US9086422B2 (en) 2008-12-10 2015-07-21 Alltech Associates, Inc. Chromatography systems and system components
US9579662B2 (en) 2010-08-27 2017-02-28 Aerosol Dynamics Inc. Condensation-evaporator nanoparticle charger
US9610531B2 (en) 2010-08-27 2017-04-04 Aerosol Dynamics Inc. Wick wetting for water condensation systems
DE102018210643A1 (en) 2018-06-28 2020-01-16 Karlsruher Institut für Technologie Method and device for determining a concentration of aerosol particles in a carrier gas
EP3637087A1 (en) 2018-10-12 2020-04-15 Université Paris Est Créteil Val De Marne Condensation particle counter
US11029240B2 (en) 2018-10-12 2021-06-08 Aerosol Dynamics Inc. Wick moisture sensor for airborne particle condensational growth systems
US11237091B2 (en) 2018-11-01 2022-02-01 Aerosol Dynamics Inc. Humidity conditioning for water-based condensational growth of ultrafine particles
US11662280B2 (en) 2017-12-29 2023-05-30 The Regents Of The University Of Colorado, A Body Corporate Hi-fidelity bioaerosol condensation capture directly into genomic preservatives

Citations (2)

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US3592546A (en) * 1969-11-21 1971-07-13 Robert A Gussman Condensation nuclei detector
US3694085A (en) * 1970-09-10 1972-09-26 Environment One Corp Mixing type condensation nuclei meter

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Publication number Priority date Publication date Assignee Title
US3592546A (en) * 1969-11-21 1971-07-13 Robert A Gussman Condensation nuclei detector
US3694085A (en) * 1970-09-10 1972-09-26 Environment One Corp Mixing type condensation nuclei meter

Cited By (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3512854A1 (en) * 1984-04-12 1985-10-17 United States Department Of Energy, Washington, D.C. DEVICE AND METHOD FOR SAMPLING SUBMICRON PARTICLES
US4790650A (en) * 1987-04-17 1988-12-13 Tsi Incorporated Condensation nucleus counter
WO1989008245A1 (en) * 1988-03-02 1989-09-08 Pacific Scientific Company Device for enlarging aerosol particles by coating them with liquid
FR2628210A1 (en) * 1988-03-02 1989-09-08 Commissariat Energie Atomique AEROSOL PARTICLE ENHANCER BY LIQUID COATING
US4950073A (en) * 1989-02-10 1990-08-21 Pacific Scientific Company Submicron particle counting enlarging the particles in a condensation based growth process
US5026155A (en) * 1989-09-06 1991-06-25 Air Products And Chemicals, Inc. Process for sizing particles using condensation nucleus counting
EP0416472A3 (en) * 1989-09-06 1991-09-25 Air Products And Chemicals, Inc. Process for sizing particles using condensation nucleus counting
EP0416472A2 (en) * 1989-09-06 1991-03-13 Air Products And Chemicals, Inc. Process for sizing particles using condensation nucleus counting
US5118959A (en) * 1991-05-03 1992-06-02 Tsi Incorporated Water separation system for condensation particle counter
US5578995A (en) * 1994-01-25 1996-11-26 Chemtrac Systems, Inc. Method of monitoring and controlling condensate quality
US5659388A (en) * 1996-09-11 1997-08-19 Vlsi Standards, Inc. Method and apparatus for operating a condensation nucleus counter with improved counting stability and accuracy over a variable detection threshold
WO1998011418A1 (en) * 1996-09-11 1998-03-19 Vlsi Standards, Inc. Condensation nucleus counter
US6125845A (en) * 1997-08-29 2000-10-03 Tsi Incorporated Respirator fit-testing with size selected aerosol
US5903338A (en) * 1998-02-11 1999-05-11 Particle Measuring Systems, Inc. Condensation nucleus counter using mixing and cooling
US6469780B1 (en) 1998-12-21 2002-10-22 Air Products And Chemicals, Inc. Apparatus and method for detecting particles in reactive and toxic gases
WO2001027589A1 (en) * 1999-10-12 2001-04-19 California Institute Of Technology Fast mixing condensation nucleus counter
US6567157B1 (en) 1999-10-12 2003-05-20 California Institute Of Technology Fast mixing condensation nucleus counter
US6712881B2 (en) 2002-01-30 2004-03-30 Aerosol Dynamics Inc. Continuous, laminar flow water-based particle condensation device and method
DE10392241B4 (en) * 2002-01-30 2009-03-05 Aerosol Dynamics Inc., Berkeley Continuous water-based laminar flow particle condensation apparatus and method
US6639671B1 (en) 2002-03-01 2003-10-28 Msp Corporation Wide-range particle counter
US20030202169A1 (en) * 2002-04-24 2003-10-30 Liu Benjamin Y.H. Compact, high-efficiency condensation nucleus counter
US6829044B2 (en) 2002-04-24 2004-12-07 Msp Corporation Compact, high-efficiency condensation nucleus counter
US20060048783A1 (en) * 2004-09-09 2006-03-09 Msp Corporation Personal mask test system
WO2006029367A2 (en) * 2004-09-09 2006-03-16 Msp Corporation A personal mask test system
WO2006029367A3 (en) * 2004-09-09 2007-03-08 Msp Corp A personal mask test system
US7325441B2 (en) 2004-09-09 2008-02-05 Msp Corporation Personal mask test system
US20070242261A1 (en) * 2005-08-25 2007-10-18 Msp Corporation Aerosol measurement by dilution and particle counting
US7363828B2 (en) 2005-08-25 2008-04-29 Msp Corporation Aerosol measurement by dilution and particle counting
US20080083274A1 (en) * 2006-10-10 2008-04-10 Hering Susanne V High saturation ratio water condensation device and method
US7736421B2 (en) 2006-10-10 2010-06-15 Aerosol Dynamics Inc. High saturation ratio water condensation device and method
US20080152547A1 (en) * 2006-12-22 2008-06-26 Thermo Electron Corporation Devices, methods, and systems for detecting particles in aerosol gas streams
US7777867B2 (en) 2006-12-22 2010-08-17 Thermo Fisher Scientific Devices, methods, and systems for detecting particles in aerosol gas streams
US20100263731A1 (en) * 2006-12-22 2010-10-21 Thermo Fisher Scientific Methods for detecting particles in aerosol gas streams
US8194234B2 (en) 2006-12-22 2012-06-05 Thermo Fisher Scientific Inc. Methods for detecting particles in aerosol gas streams
US8305581B2 (en) 2007-12-05 2012-11-06 Alltech Associates, Inc. Methods and apparatus for analyzing samples and collecting sample fractions
US8192523B1 (en) 2008-02-22 2012-06-05 Tsi Incorporated Device and method for separating and increasing the concentration of charged particles in a sampled aerosol
US9086422B2 (en) 2008-12-10 2015-07-21 Alltech Associates, Inc. Chromatography systems and system components
US8305582B2 (en) 2009-09-01 2012-11-06 Alltech Associates, Inc. Methods and apparatus for analyzing samples and collecting sample fractions
US9322813B2 (en) 2009-09-01 2016-04-26 Alltech Associates, Inc. Methods and apparatus for analyzing samples and collecting sample fractions
US9579662B2 (en) 2010-08-27 2017-02-28 Aerosol Dynamics Inc. Condensation-evaporator nanoparticle charger
US9610531B2 (en) 2010-08-27 2017-04-04 Aerosol Dynamics Inc. Wick wetting for water condensation systems
US11662280B2 (en) 2017-12-29 2023-05-30 The Regents Of The University Of Colorado, A Body Corporate Hi-fidelity bioaerosol condensation capture directly into genomic preservatives
DE102018210643A1 (en) 2018-06-28 2020-01-16 Karlsruher Institut für Technologie Method and device for determining a concentration of aerosol particles in a carrier gas
US11474019B2 (en) 2018-06-28 2022-10-18 Karlsruher Institut Fur Technologie Method and apparatus for determining a concentration of aerosol particles in a carrier gas
DE102018210643B4 (en) 2018-06-28 2023-08-24 Karlsruher Institut für Technologie Method and device for determining a concentration of aerosol particles in a carrier gas
EP3637087A1 (en) 2018-10-12 2020-04-15 Université Paris Est Créteil Val De Marne Condensation particle counter
WO2020074732A1 (en) 2018-10-12 2020-04-16 Universite Paris Est Creteil Val De Marne Condensation particle counter
US11029240B2 (en) 2018-10-12 2021-06-08 Aerosol Dynamics Inc. Wick moisture sensor for airborne particle condensational growth systems
US11237091B2 (en) 2018-11-01 2022-02-01 Aerosol Dynamics Inc. Humidity conditioning for water-based condensational growth of ultrafine particles

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