Massachusetts Institute of Technology

James R Melcher

Karim Zahedi

Neil J Goldfine

Jeffrey C Alexander

Stuart Inkpen

Nam Pyo Suh

Markus Zahn

Kenneth S Sachar

Lewis Erwin, Ii

Christopher A Rotz

James F Hoburg

Alfred J Morin, Ii

Thomas W Johnson

Mark C Zaretsky

Apparatus and methods are disclosed which provide increased sensitivity, selectivity and dynamic range for non-contact measurement of actual physical and/or kinematic properties of conducting and magnetic materials. The apparatus and methods are based upon various methods for increasing sensitivity, selectivity and dynamic range through proper construction of a magnetometer sensor and for proper selection of operating point parameters for the application. A measurement apparatus for measuring one or more MUT properties includes an electromagnetic winding structure which, when driven by an electric signal, imposes a magnetic field in the MUT and senses an electromagnetic response. An analyzer is provided for applying the electric signal to the winding structure. A property estimator is coupled to the winding structure and translates sensed electromagnetic responses into estimates of one or more preselected properties of the material.

Apparatus and method for obtaining increased sensitivity, selectivity and dynamic range in property measurement using magnetometers

Apparatus and methods for obtaining increased sensitivity, selectivity and dynamic range in property measurement using magnetometers

Devices and analytical techniques are disclosed for measuring spatial profiles of complex permeability and conductivity of a material by multiple wavenumber interrogations. Coil array structures are disclosed which define a number of different fundamental wavelengths (or wavenumbers). Spatially periodic interrogation signals (of temporal frequency '.omega.') from the coil array structures are attenuated by varying degrees in the material undergoing analysis, depending on the wavenumber ('k'), thereby permitting the derivation of composite complex permeability/conductivity profile.

Apparatus and methods for measuring permeability and conductivity in

Multicolored tone paint compositions containing flat metallic particles are produced by subjecting an electrically conductive substrate coated with the paint composition, while wet, to ion current. The field caused by the corona current vertically orients the metallic particles in that portion of the paint subjected to the current while the metallic particles in the unexposed paint remain in horizontal orientation.

Method for inducing color shift in metallic paints

The density of charge entrained in fluids such as oils in transformer systems, capacitors, cables, pumps and fuel transfer systems is measured by introducing the oil into a conductive container which expands in volume to receive the fluid without expelling any fluid. The container is shielded by a grounded conductor which prevents inducement of charge on the container by external sources. By measuring the current between the conducting expandable container and the surrounding shield and accounting for the effects of the charge induced on the outer wall of the container by its own induced voltage, the net charge entrained in the fluid as it is brought into the container is deduced. Extraneous effects of conduction and electrokinetic currents are automatically excluded from the measurement. The oil is then automatically returned to the transformer system by the contraction of the conductive container so that the measurement can be repeated without accumulating an inventory of fluid.

Method and apparatus for measurement of charge entrained in fluids

Article of manufacture

Devices and analytical techniques are disclosed for measuring the spatial profile of permittivity of a material by multiple wavenumber interrogations. Electrode structures are disclosed which define a number of different fundamental wavelengths (or wavenumbers). Spatially periodic interrogation signals (of temporary frequency '.omega.') from the electrode structures are attenuated to varying degrees by the material undergoing analysis, depending upon the wavenumber ('k'), thereby permitting the derivation of a composite dielectric profile.

Apparatus and methods for measuring permittivity in materials

A fluid mixing apparatus having means for producing vortex-like motions of the fluids introduced therein, one embodiment of such an apparatus, for example, using two concentrically mounted inner and outer members, preferably cylindrical, moveable relative to each other at rotational speeds such as to produce the desired vortex-like motions of the fluids introduced into the region therebetween. In one embodiment thereof, the vortex-like motions may be obtained at relatively low rotational speeds by the use of V-shaped grooves on the inner member. In addition, suitable means can further be used to generate a de-stabilizing force for the fluids in a direction substantially perpendicular to the velocity streamlines thereof to further enhance the mixing effectiveness and to improve the quality of the mix, such de-stabilizing force in one embodiment, for example, being generated by the application of an electric field across the region between the inner and outer members.

Fluid mixing apparatus

A fluidized bed, particulate collector system wherein, in one embodiment, the bed particles have applied thereto at the surface thereof, an additive that serves to adhere particulate, once collected, to the bed particles. The bed particles and/or additive may be combustible or may be incombustible. In one embodiment, the system includes two fluidized beds, in tandem, the first of which collects particulate mostly in the supermicron sizes and the second of which is an electrofluidized bed that collects particulate mostly in the submicron sizes.

Fluidized bed particulate collectors

An electrofluidized bed agglomerator and method of agglomerating which comprises agglomerating submicron (and/or supermicron) particulates with a liquid, said liquid acting as a bond between particulates of the agglomerate thus formed to maintain the integrity thereof.

Electrofluidized bed agglomerator and method of agglomerating

Apparatus for effecting the function conventionally performed by the distributor plate in static, packed, or fluidized beds wherein the bed particles are supported or stabilized by an electric field imposed by an external source of electric potential.

Apparatus for electrical support and stabilization of static, packed,

Apparatus for the high performance collection of gas entrained particulate, especially submicron particulate, consisting of a fluidized bed of collection sites with an electric field imposed on the bed so that the particulate to be collected, which is charged prior to entering the bed with the fluidizing gas, is electrically induced to agglomerate with the bed particles and the collected matter is removed in a fluidized state with the bed particles, which can consist of the collected material itself.

Growing community of inventors

Lexington, MA, United States of America

James R Melcher