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.

Methods for determining a radius of gyration of a particle in solution using a light scattering detector are provided. The method may include passing the solution through a flowpath in a sample cell, determining respective angular normalization factors for first and second angles of the detector, obtaining a first scattering intensity of the particle in solution at the first angle, obtaining a second scattering intensity of the particle in solution at the second angle, obtaining a 10° scattering intensity of the particle in solution at an angle of about 10°, determining a first particle scattering factor, determining a second particle scattering factor, plotting an angular dissymmetry plot, fitting a line to the angular dissymmetry plot, determining a slope of the line at a selected location on the line, determining the radius of gyration of the particle in solution from the slope of the line, and outputting the radius of gyration.

A smoke detector for an air duct includes a photoelectric detection system and an air flow pathway in fluid communication with the air duct. The air flow pathway includes an inlet, an optic tube, and an outlet. The photoelectric detection system includes a circuit board having at least one light emitter and at least one light receiver mounted thereon. The optic tube passes through the circuit board and between the at least one light emitter and at least one light receiver.

Systems and methods for uniquely identifying fluid-phase products by endowing them with fingerprints composed of dispersed colloidal particles, and by reading out those fingerprints on demand using Total Holographic Characterization. A library of chemically inert colloidal particles is developed that can be dispersed into soft materials, the stoichiometry of the mixture encoding user-specified information, including information about the host material. Encoded information then can be recovered by high-speed analysis of holographic microscopy images of the dispersed particles. Specifically, holograms of individual colloidal spheres are analyzed with predictions of the theory of light scattering to measure each sphere's radius and refractive index, thereby building up the distribution of particle properties one particle at a time. A complete analysis of a colloidal fingerprint requires several thousand single-particle holograms and can be completed in ten minutes.

A particle characterization apparatus comprising: a light source for illuminating a sample with a light beam; a detector arranged to detect scattered light from the interaction of the light beam with the sample; and a focus tuneable lens arranged to collect the scattered light for the detector from a scattering volume and/or to direct the light beam into the sample.

The particle sensor device comprises a substrate, a photodetector, a dielectric on or above the substrate, a source of electromagnetic radiation, and a through-substrate via in the substrate. The through-substrate via is exposed to the environment, in particular to ambient air. A waveguide is arranged in or above the dielectric so that the electromagnetic radiation emitted by the source of electromagnetic radiation is coupled into a portion of the waveguide. A further portion of the waveguide is opposite the photodetector, so that said portions of the waveguide are on different sides of the through-substrate via, and the waveguide traverses the through-substrate via.

A smoke detector for an air duct includes a photoelectric detection system and an air flow pathway in fluid communication with the air duct. The air flow pathway includes an inlet, an optic tube, and an outlet. The photoelectric detection system includes a circuit board having at least one light emitter and at least one light receiver mounted thereon. The optic tube passes through the circuit board and between the at least one light emitter and at least one light receiver.

A particle characterization apparatus is disclosed comprising: a sample cell for holding a sample, a light source for producing a light beam for illuminating the sample in the sample cell, thereby producing scattered light by the interaction of the light beam with the sample; a focussing lens for focussing the light beam within the sample; and a detector for detecting the backscattered light along a detection optical path that intersects the focussed light beam within the sample. The intersection of the light beam and the detection optical path in the sample define a detection region. The apparatus comprises an optical arrangement for varying the volume of the detection region.

Systems and methods for monitoring air particulate matter are provided herein that capture particles from the air for analysis. Particles are captured using electrostatic and/or mechanical means to deflect particles toward a substrate. Electrostatic precipitation causes charged carriers to deflect towards a charged substrate. Filtration-based means employ filters and/or fibers to capture particles from air flowing therethrough. A sensor such as a camera is used to read the captured particles. An illumination source directs light towards the substrate, causing the particles to scatter light, which the sensor can detect and derive information or imaging therefrom, which can also be used for further particle or pollution analyses. The substrate can be replenished using electrostatic techniques such as reverse electrostatic force, or mechanical means such as cleaning using a brush or replacing a tape substrate. Dynamic PM monitoring detects and makes adjustments such as those related to air volume, imaging characteristics and substrate replenishment.

Stationary devices employing quadrature phase analysis light scattering are provided, to aid in the determination of the magnitude and polarity of electrophoretic mobility and zeta potential of particles in colloids. The devices use an optical quadrature interferometer with an electrophoresis sample chamber containing sample particles undergoing electrophoresis, the optical quadrature interferometer being configured to generate a quadrature signal. The phase of the quadrature signal may be analyzed at the frequency of the sample chamber electric field to estimate displacements and directions of the particles. The estimates can be used to determine a central value of the magnitude of the electrophoretic mobility, as well as its polarity. Particles having low electrophoretic mobility, or that may be adversely affected by high electric fields, can be analyzed, and constraints on vibration and light source coherence length may be relaxed. A phase modulator or frequency shifter is not required.