A particle detector for rapidly detecting and identifying sub 20 nm particles in Ultra Pure Water (UPW) is disclosed. The detector has a nano particle extractor, a nanoparticle collector, and a tracer particle introducer. The extractor limits the size of droplets output to a predetermined size. The extractor includes (1) a liquid sample inlet, (2) a nebulizer connected to the liquid sample inlet (the nebulizer has a gas supply, and an outlet), (3) an impactor arranged to receive material output from the nebulizer, (4) an evaporator connected to the nebulizer and impactor for providing an aerosol at the extractor outlet, and (5) an aerosol connected to the evaporator. The collector us connected to the extractor and has: (1) a collector inlet connected to the aerosol outlet of the extractor, (2) a vapor condensation growth tube connected to the collector inlet, and (3) a repositionable particle capture plate arranged to receive material output from the growth tube at spatially varying positions. The tracer particle introducer is connected to the liquid sample inlet of the extractor. It includes a tracer particle supply connected to a pump which is connected to the extractor. A method for rapid identification of sub−20 nm particles in UPW is also disclosed.

A system and method to measure a size distribution of particles based on their electrical mobility. The method includes: introducing, via a sheath flow inlet, a particle free sheath flow into a chamber formed by two parallel walls which are separated by a gap, the chamber having a width and a length, the sheath flow having a direction along the length of the chamber and flowing a laminar manner; introducing an aerosol sample flow into the chamber downstream of the sheath inlet such that the aerosol sample flow joins the particle free sheath flow in a laminar manner; applying an electric field between the two parallel walls of the chamber, the field having a strength which varies across the width of the chamber; extracting an output aerosol flow through a first outlet downstream of the sample inlet; and outputting an excess flow equal to a sum of the sheath flow and aerosol sample flow minus the output aerosol flow. The method may also include: passing the output aerosol flow through a growth cell in a laminar manner, the growth cell having a region of wetted walls with two or more temperature regions such that the particles within the output aerosol flow grow by condensation to form droplets, and such that relative positions of droplets are indicative of particle electrical mobility; and counting and capturing a spatial position of individual droplets exiting the growth cell.

A stream including at least one of solid CO.sub.2 particles or CO.sub.2 droplets is directed toward an article including surface particles. The stream causes at least a portion of the surface particles on the article to dislodge from a surface of the article. A purge cycle to transport at least a portion of the dislodged surface particles away from the surface of the article is initiated. The purge cycle includes generating a laminar flow at a first velocity for a first time period and subsequently generating a laminar flow at a second velocity for a second time period. A determination is made of whether a number of particles transported away from the surface of the article satisfies a particle criterion. In response to a determination that the number of particles transported away from the article does not satisfy the criterion, the purge cycle is re-initiated.

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.

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.

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.

Disclosed herein is a method comprising directing, from a distribution unit, a stream comprising at least one of solid CO.sub.2 particles or CO.sub.2 droplets toward an article, wherein the article comprises a plurality of surface particles, and wherein the stream comprising at least one of solid CO.sub.2 particles or CO.sub.2 droplets causes at least a portion of the plurality of surface particles on the article to dislodge from the surface of the article; collecting, on a surface of a substrate having a pre-determined initial state comprising initial surface particles on the surface of the substrate or a real-time aerosol sampling unit, at least some of the portion of the plurality of surface particles dislodged from the surface of the article; analyzing the surface of the substrate after performing the collecting; and determining at least one of a size, a morphology, a chemical composition, a particle number concentration, or a particle size distribution of the portion of the plurality of surface particles that were dislodged from the surface of the article and collected on the surface of the substrate.

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.

A particle growth apparatus includes a temperature-controlled humidifier coupled to a water-based condensation growth system. The humidifier may include a tube of sulfonated tetrafluoroethylene-based fluoropolymer-copolymer and surrounded by a region containing water or water vapor. The apparatus includes a wetted wick and wick sensor in the condensation growth system, configured such that the gas sample flows through the sulfonated tetrafluoroethylene-based fluoropolymer-copolymer tube into the condensation growth system.

A method and apparatus to create water vapor supersaturation and particulate counts from an air sample. The method and apparatus include introducing an air sample into a chamber by passing a flow into the chamber through the inlet by pumping at the outlet. The method further includes closing the inlet while continuing the pumping to exhaust the air sample from the chamber through the outlet. The pumping is performed at a rate operable to reduce pressure inside the chamber such that the air sample in the central portion of the chamber cools, and water vapor from walls of the chamber has time to diffuse into the air sample in the chamber from the walls. The cycles are repeated by continuously repeating the introducing and closing. The walls of the chamber may be wet or dry.