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: A system includes a polymer bag, a fluid network, a saturation block, and a wick. The polymer bag has a sealed envelope and a fitment. The fluid network is coupled to the fitment. The saturation block has a fluid inlet coupled to the fluid network and has a wick chamber. The wick is configured for disposition in the wick chamber.

Abstract: Various embodiments include methods and apparatuses to reduce false-particle counts in a water-based condensation particle counter (CPC). In one embodiment, a cleanroom CPC has three parallel growth tube assemblies. A detector is coupled to an outlet of each of the three parallel growth tube assemblies, and is used to compare the particle concentrations measured from each of the three growth tube assemblies with remaining ones of the three growth tube assemblies. An algorithm compares the counts from the three detectors and determines when the particles counted are real and when they are false counts. Any real particle event shows up in all three detectors, while false counts will only be detected by one detector. Statistics are used to determine at which particle count levels the measured counts are considered to be real versus false. Other methods and apparatuses are disclosed.

Abstract: There is disclosed a handheld air flow velocity measurement probe that includes a bridge circuit assembly having an airflow velocity sensor that is a resistance temperature detector (RTD) and a digitally controlled resistive element to dynamically adjust and maintain the resistance of the velocity sensor within the overheat temperature predefined range. The velocity measurement also uses a separate temperature sensor to sense the temperature of the air or gas flow. A humidity sensor is also included remote from the other sensors to measure humidity in the gas flow to be measured. All of the above described components are housed at a probe tip instead of a base as in most standard handheld probes and the digital interface at the probe tip allows the user to replace a bulky, expensive telescoping antenna with stackable extender scheme.

Abstract: Various embodiments include an exemplary apparatus and method for insitu calibration of multiple flow-sensing devices within a dilution system. In one example, a calibration and dilution system includes a first mass-flow device to serve as a global reference, a second mass-flow device configured to be coupled to and provide a supply of clean gas to a primary diluter, and a third mass-flow device configured to be coupled to and provide a supply of clean gas to a secondary diluter, where the diluters are pneumatically coupled to one another through a gas-supply line. Multiple valves are coupled to at least the mass-flow devices and the diluters. The calibration and dilution system is arranged so that the mass-flow controllers can be calibrated in-situ without having to remove any of the mass-flow controllers from the calibration and dilution system. Other apparatuses, designs, and methods 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 methods and systems to measure and calibrate an optical particle spectrometer for reporting mass concentration. In one embodiment, an optical particle spectrometer is used to measure a concentration of particulate matter in a sampled particle-laden airstream. A particle diverter, in fluid communication with the spectrometer, diverts at least a portion of the particle-laden airstream at predetermined intervals. In one example, a mass filter receives the portion of the particle-laden airstream and filters a fraction of the particles within the airstream that are above a predetermined particle size. A mass sensor measures a mass of the fraction of the particles received from the mass filter or from the particle diverter and uses a calibration communication loop to provide the measured mass to the spectrometer to apply a correction factor to report mass concentration from the optical particle spectrometer. 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 methods and systems to dilute a sampled particle-laden aerosol stream in a recirculating type of aerosol diluter system. In one embodiment, a system to dilute a sampled aerosol stream includes an aerosol sample inlet. A primary diluter device includes a first inlet to receive the aerosol stream and a second inlet to receive a filtered portion of the aerosol stream and combining the filtered portion with an additional sampled aerosol stream. A flow diverter device splits at least the sampled aerosol stream into a first portion of the sampled aerosol stream and a remaining portion of the sampled aerosol stream. A filter receives the remaining portion of the sampled aerosol stream and provides a filtered aerosol stream to the second inlet of the primary diluter device. Other methods and apparatuses are disclosed.

Abstract: An apparatus and method for use in determining one or more fluid flow properties of a fluid in a conduit is disclosed. The apparatus includes a substrate including a barrier, a first flow sensor coupled to the substrate and a second flow sensor coupled to the substrate. The first flow sensor is located at a first sensor distance from a first barrier surface, and the second flow sensor is located a second sensor distance from the second barrier surface. The first sensor distance is substantially equal to the second sensor distance. In operation, the first flow sensor produces a first sensor signal, and the second flow sensor produces a second sensor signal. The direction of flow for the fluid is determined by comparing the first sensor signal to the second sensor signal.

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 composite wicks for ultra-low noise condensation particle counters (CPCs). In one embodiment, a composite wick includes a first porous material having a first pore density, with the first porous material further having a first surface and an opposing second surface. A second porous material is in fluid communication with the first porous material and has a first surface with an area substantially the same as an area of the first surface of the first porous material. The first surface of the second porous material is substantially in contact with the first surface of the first porous material. The second porous material has a pore density that is dissimilar the first pore density of the first material. The first material and the second material are configured to provide vapor from a liquid to a fluid-based particle counter. Other apparatuses are disclosed.

Abstract: Various embodiments include an exemplary design of an apparatus and related process to reduce or eliminate de-gassing from a liquid precursor during dispensing of the liquid precursor under vacuum. In one embodiment, the apparatus includes a liquid-flow controller configured to be coupled to a liquid-supply vessel containing the liquid precursor, and at least one valve hydraulically coupled downstream of and to the liquid-flow controller by a liquid line. The at least one valve is to be opened and closed to maintain a minimum pressure that is sufficiently high enough to reduce or prevent degassing of the liquid precursor throughout the liquid line. An atomizer is hydraulically coupled downstream of and to the at least one valve. The atomizer can produce droplets of the liquid precursor and is further to be coupled on a downstream side to a vacuum source. Other methods and apparatuses are disclosed.

Abstract: A particle velocimetry system and algorithm are provided for executing a particle reconstruction to determine three-dimensional positions of particles in a particle laden fluid flow from two-dimensional flow images generated by two-dimensional image sensors; generate a three-dimensional particle distribution from the three-dimensional position; and execute a recursive loop for performing further iterations of particle reconstruction and generation of three-dimensional particle distributions, with recursive iterations of particle reconstruction executed with the use of particle property data obtained from the prior executed iteration of particle reconstruction.

Abstract: The respirator fit monitor described herein can be worn continuously by users so as to provide an indication as to how well their masks are fitting during use, thereby providing quantitative, wearable fit testers available for continuous use in real-life situations. The monitor includes a low-cost optical particle sensor assembly and controller unit for performing mask fit tests by comparing particle concentrations inside and outside of the mask. The fit test monitor is low cost and wearable, capable of dual sampling, capable of fit factor ratios well above 100, is battery powered and provides near real time measurements with a means for indicating the fit of the mask. The system includes wired or wireless communications for data logging, analysis and display capabilities.

Abstract: A system includes a first and second condensation particle counter, each counter having an inlet port, a growth column, and an optical element for counting particles detected at the respective inlet ports. The counters are configured to include a wick in which the wick is wetted by water. A differential pressure sensor is coupled to the first inlet port and coupled to the second inlet port. The sensor is configured to provide a pressure signal. A processor is coupled to memory and configured to receive the first signal, the second signal, and the pressure signal and generate an output corresponding to a ratio of the first signal and the second signal and correlate the ratio with the pressure signal. A housing is configured to receive the first counter, the second counter, the differential pressure sensor, the processor, and the memory.

Abstract: Various embodiments include an exemplary design of an apparatus and related process to reduce or eliminate de-gassing from a liquid precursor during dispensing of the liquid precursor under vacuum. In one embodiment, the apparatus includes a liquid-flow controller configured to be coupled to a liquid-supply vessel containing the liquid precursor, and at least one valve hydraulically coupled downstream of and to the liquid-flow controller by a liquid line. The at least one valve is to be opened and closed to maintain a minimum pressure that is sufficiently high enough to reduce or prevent degassing of the liquid precursor throughout the liquid line. An atomizer is hydraulically coupled downstream of and to the at least one valve. The atomizer can produce droplets of the liquid precursor and is further to be coupled on a downstream side to a vacuum source. 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: A seed dispensing system is provided with a photoelectric sensor for monitoring the dispensing of seeds from a seed dispenser comprising a discharge conveyor with conveyor flights that transport seeds through the seed dispenser. The sensor outputs a signal representative of obstructions to the flow of light in an optical path of the sensor, and a computing unit is adapted to distinguish portions of the output signal that are attributable to the passage of one or more seeds from portions of the output signal that are attributable to the passage of a conveyor flight.

Abstract: Various embodiments include methods and apparatuses to reduce false-particle counts in a water-based condensation particle counter (CPC). In one embodiment, a cleanroom CPC has three parallel growth tube assemblies. A detector is coupled to an outlet of each of the three parallel growth tube assemblies, and is used to compare the particle concentrations measured from each of the three growth tube assemblies. An algorithm compares the counts from the three detectors and determines when the particles counted are real and when they are false counts. Any real particle event shows up in all three detectors, while false counts will only be detected by one detector. Statistics are used to determine at which particle count levels the measured counts are considered to be real versus false. Other methods and apparatuses are disclosed.