Abstract: An apparatus and method for the aerosolization of powders is disclosed. The invention includes a chamber in which a cloud of aerosolized powder is formed, the cloud having a relatively even distribution of powder particles. A Bernoulli tube may be used to extract powder from the powder cloud when the powder cloud reaches its equilibrium height. Adjustment of the air flow rate into the Bernoulli tube may be used to control the flow rate of powder out of the disclosed device.

Abstract: A powder spray gun, and method for using same, is disclosed. The powder gun includes a corona discharge tip and mesh screen within the passage for powder flow. A potential is applied to the corona discharge tip, resulting in an electric field between the corona discharge tip and mesh screen. This electric field efficiently charges powder particles passing through the spray gun, but the mesh screen blocks most of the free ions that are generated by the corona discharge tip. Any free ions that pass through the mesh screen are captured by a conductive end piece on the spray gun. A potential difference is applied between the end of the spray gun and the workpiece to guide the charged powder particles to the workpiece.

Abstract: A new class of methods for characterizing particles is described along with associated apparatuses. These methods are called modulated dynamic light scattering (MDLS) methods because they utilize time and space modulations of the incident or scattered light as well as modulations caused by random Brownian motions of the particles, for example, to measure particular properties. The autocorrelation function of the scattered light signal from a particle is measured to provide a highly resolved signature even when the signal is buried in noise. The dynamics of the scattered light signal from a suspended particle undergoing random Brownian translations and rotations is analyzed to obtain the relationship of the particle's properties to its autocorrelation function signature. By comparison of the theoretical and measured functions, properties of a particle suspended in a (1) liquid, (2) gas, or (3) rarefied gas can be determined.

Abstract: A new class of methods for characterizing particles is described along with associated apparatuses. These methods are called modulated dynamic light scattering (MDLS) methods because they utilize time and space modulations of the incident or scattered light as well as modulations caused by random Brownian motions of the particles, for example, to measure particular properties. The autocorrelation function of the scattered light signal from a particle is measured to provide a highly resolved signature even when the signal is buried in noise. The dynamics of the scattered light signal from a suspended particle undergoing random Brownian translations and rotations is analyzed to obtain the relationship of the particle's properties to its autocorrelation function signature. By comparison of the theoretical and measured functions, properties of a particle suspended in a (1) liquid, (2) gas, or (3) rarefied gas can be determined.