Abstract: A measurement system includes an atomizer, an impactor, a particle counter, and a discharge reservoir. The atomizer has a liquid intake port and a gas intake port configured to aerosolize a liquid received at the liquid intake port. The impactor has an inlet coupled to the atomizer and has a first output port and a second output port. The impactor is configured to separate droplets wherein those droplets smaller than a selected cut point are directed to the first output port and those droplets larger than the selected cut point are directed to the second output port. The particle counter is coupled to the first output port and is configured to count particles larger than at least one particle size cut point. The discharge reservoir is coupled to the second output port.

Abstract: Various embodiments include systems and apparatuses for reducing contamination levels within optical chambers of particle-detection instruments. In one embodiment, an apparatus to reduce contamination within an optical chamber of a particle-detection instrument is described. The apparatus includes a plenum chamber to at least partially surround an aerosol-focusing nozzle of the particle-detection instrument and accept a filtered gas flow. A curtain-flow concentrating nozzle is coupled to the plenum chamber to produce a curtain flow into the optical chamber to substantially surround an aerosol flow. Other methods and systems are disclosed.

Abstract: The disclosed subject matter compensates or corrects for errors that otherwise would be present when a measurement is made on a condensation particle counting system with the only difference causing the errors being absolute pressure. The difference in absolute pressure may be due to, for example, a change in altitude in which the condensation particle counting system is located. Techniques and mechanisms are disclosed to compensate for changes in particle count, at a given particle diameter, for changes in sampled absolute pressure at which measurements are taken. Other methods and apparatuses are disclosed.

Abstract: Various embodiments include an exemplary design of a high-temperature condensation particle counter (HT-CPC) having particle-counting statistics that are greatly improved over prior art systems since the sample flow of the disclosed HT-CPC is at least eight times greater than the prior art systems. In one embodiment, the HT-CPC includes a saturator block to accept directly a sampled particle-laden gas flow, a condenser block located downstream and in fluid communication with the saturator block, an optics block located downstream and in fluid communication with the condenser block, and a makeup-flow block having a concentric-tube design located in fluid communication with and between the condenser block and the optics block. The makeup-flow block being configured to reduce volatile contents from re-nucleating in the optics block. Other designs and apparatuses are disclosed.

Abstract: A measurement system includes an atomizer, an impactor, a particle counter, and a discharge reservoir. The atomizer has a liquid intake port and a gas intake port configured to aerosolize a liquid received at the liquid intake port. The impactor has an inlet coupled to the atomizer and has a first output port and a second output port. The impactor is configured to separate droplets wherein those droplets smaller than a selected cut point are directed to the first output port and those droplets larger than the selected cut point are directed to the second output port. The particle counter is coupled to the first output port and is configured to count particles larger than at least one particle size cut point. The discharge reservoir is coupled to the second output port.

Abstract: Various embodiments include an exemplary design of a high-temperature condensation particle counter (HT-CPC) having particle-counting statistics that are greatly improved over prior art systems since the sample flow of the disclosed HT-CPC is at least eight times greater than the prior art systems. In one embodiment, the HT-CPC includes a saturator block to accept directly a sampled particle-laden gas flow, a condenser block located downstream and in fluid communication with the saturator block, an optics block located downstream and in fluid communication with the condenser block, and a makeup-flow block having a concentric-tube design located in fluid communication with and between the condenser block and the optics block. The makeup-flow block being configured to reduce volatile contents from re-nucleating in the optics block. Other designs and apparatuses are disclosed.

Abstract: Various embodiments include systems and apparatuses for reducing contamination levels within optical chambers of particle-detection instruments. In one embodiment, an apparatus to reduce contamination within an optical chamber of a particle-detection instrument is described. The apparatus includes a plenum chamber to at least partially surround an aerosol-focusing nozzle of the particle-detection instrument and accept a filtered gas flow. A curtain-flow concentrating nozzle is coupled to the plenum chamber to produce a curtain flow into the optical chamber to substantially surround an aerosol flow. Other methods and systems are disclosed.

Abstract: Various embodiments include an exemplary design of a high-temperature condensation particle counter (HT-CPC) having particle-counting statistics that are greatly improved over prior art systems since the sample flow of the disclosed HT-CPC is at least eight times greater than the prior art systems. In one embodiment, the HT-CPC includes a saturator block to accept directly a sampled particle-laden gas flow, a condenser block located downstream and in fluid communication with the saturator block, an optics block located downstream and in fluid communication with the condenser block, and a makeup-flow block having a concentric-tube design located in fluid communication with and between the condenser block and the optics block. The makeup-flow block being configured to reduce volatile contents from re-nucleating in the optics block. Other designs and apparatuses are disclosed.

Abstract: There is disclosed a field calibratable particle sensor solution in a low-cost, very compact form factor. This makes a low-cost sensor more accurate for low-concentration pollution measurements and decreases the cost of pollution measurement systems having a wide geographic coverage. In a related embodiment, the invention illustrates a method and system to remotely and automatically calibrate one or more of the low cost sensors disclosed herein as well as other commercially available sensors (such as optical particle counters, photometers etc.) against a reference instrument (such as a beta attenuation monitor) which may or may not be physically located in the same place as the individual sensors. The method may require minimum (or no) user interaction and the calibration period is adjustable periodically.

Abstract: The disclosed subject matter compensates or corrects for errors that otherwise would be present when a measurement is made on a condensation particle counting system with the only difference causing the errors being absolute pressure. The difference in absolute pressure may be due to, for example, a change in altitude in which the condensation particle counting system is located. Techniques and mechanisms are disclosed to compensate for changes in particle count, at a given particle diameter, for changes in sampled absolute pressure at which measurements are taken. Other methods and apparatuses are disclosed.

Abstract: There is disclosed a field calibratable particle sensor solution in a low-cost, very compact form factor. This makes a low-cost sensor more accurate for low-concentration pollution measurements and decreases the cost of pollution measurement systems having a wide geographic coverage. In a related embodiment, the invention illustrates a method and system to remotely and automatically calibrate one or more of the low cost sensors disclosed herein as well as other commercially available sensors (such as optical particle counters, photometers etc.) against a reference instrument (such as a beta attenuation monitor) which may or may not be physically located in the same place as the individual sensors. The method may require minimum (or no) user interaction and the calibration period is adjustable periodically.

Abstract: There is disclosed a field calibratable particle sensor solution in a low-cost, very compact form factor. This makes a low-cost sensor more accurate for low-concentration pollution measurements and decreases the cost of pollution measurement systems having a wide geographic coverage. In a related embodiment, the invention illustrates a method and system to remotely and automatically calibrate one or more of the low cost sensors disclosed herein as well as other commercially available sensors (such as optical particle counters, photometers etc.) against a reference instrument (such as a beta attenuation monitor) which may or may not be physically located in the same place as the individual sensors. The method may require minimum (or no) user interaction and the calibration period is adjustable periodically.

Abstract: A system and a method of measuring a particle's size in a select aerosol using the optical diameter of the particle to perform a mobility and/or aerodynamic diameter conversion without any knowledge about the particle's shape and its optical properties in the aerosol being characterized. In one example embodiment of the invention, the method includes generating a set of calibration data and finding the optimal refractive index and shape that best fits the calibration data. In addition, the method includes creating a new calibration curve that provides a mobility-equivalent or aerodynamic-equivalent diameter.

Abstract: The various embodiments described herein significantly increase charge probabilities of nanoparticles by first growing them to larger droplets using a diethylene glycol-based preconditioner, neutralizing the droplets with a bipolar charger, and then removing the condensed liquid to recover the original aerosol particles. The small droplet size is an important element in reducing the amount of aerosol particles with more than one charge. The high single-charge particle probability significantly enhances the monodisperse aerosol throughput of a DMA, while the reduced multiple charge probabilities ensure high monodispersity of DMA-classified aerosols and good data quality of SMPS measurements.

Abstract: There is disclosed a field calibratable particle sensor solution in a low-cost, very compact form factor. This makes a low-cost sensor more accurate for low-concentration pollution measurements and decreases the cost of pollution measurement systems having a wide geographic coverage. In a related embodiment, the invention illustrates a method and system to remotely and automatically calibrate one or more of the low cost sensors disclosed herein as well as other commercially available sensors (such as optical particle counters, photometers etc.) against a reference instrument (such as a beta attenuation monitor) which may or may not be physically located in the same place as the individual sensors. The method may require minimum (or no) user interaction and the calibration period is adjustable periodically.

Abstract: There is disclosed a field calibratable particle sensor solution in a low-cost, very compact form factor. This makes a low-cost sensor more accurate for low-concentration pollution measurements and decreases the cost of pollution measurement systems having a wide geographic coverage. In a related embodiment, the invention illustrates a method and system to remotely and automatically calibrate one or more of the low cost sensors disclosed herein as well as other commercially available sensors (such as optical particle counters, photometers etc.) against a reference instrument (such as a beta attenuation monitor) which may or may not be physically located in the same place as the individual sensors. The method may require minimum (or no) user interaction and the calibration period is adjustable periodically.

Abstract: A system and a method of measuring a particle's size in a select aerosol using the optical diameter of the particle to perform a mobility and/or aerodynamic diameter conversion without any knowledge about the particle's shape and its optical properties in the aerosol being characterized. In one example embodiment of the invention, the method includes generating a set of calibration data and finding the optimal refractive index and shape that best fits the calibration data. In addition, the method includes creating a new calibration curve that provides a mobility-equivalent or aerodynamic-equivalent diameter.

Abstract: There is disclosed a field calibratable particle sensor solution in a low-cost, very compact form factor. This makes a low-cost sensor more accurate for low-concentration pollution measurements and decreases the cost of pollution measurement systems having a wide geographic coverage. In a related embodiment, the invention illustrates a method and system to remotely and automatically calibrate one or more of the low cost sensors disclosed herein as well as other commercially available sensors (such as optical particle counters, photometers etc.) against a reference instrument (such as a beta attenuation monitor) which may or may not be physically located in the same place as the individual sensors. The method may require minimum (or no) user interaction and the calibration period is adjustable periodically.

Abstract: A system and a method of measuring a particle's size in a select aerosol using the optical diameter of the particle to perform a mobility and/or aerodynamic diameter conversion without any knowledge about the particle's shape and its optical properties in the aerosol being characterized. In one example embodiment of the invention, the method includes generating a set of calibration data and finding the optimal refractive index and shape that best fits the calibration data. In addition, the method includes creating a new calibration curve that provides a mobility-equivalent or aerodynamic-equivalent diameter.

Abstract: The various embodiments described herein significantly increase charge probabilities of nanoparticles by first growing them to larger droplets using a diethylene glycol-based preconditioner, neutralizing the droplets with a bipolar charger, and then removing the condensed liquid to recover the original aerosol particles. The small droplet size is an important element in reducing the amount of aerosol particles with more than one charge. The high single-charge particle probability significantly enhances the monodisperse aerosol throughput of a DMA, while the reduced multiple charge probabilities ensure high monodispersity of DMA-classified aerosols and good data quality of SMPS measurements.