University of California

University of Illinois

Red Creamery LLC

Uchicago Argonne, LLC

Igor Paprotny

Ron Goldman

Richard M White

Christopher Silvio Cosentino

Dmitry Yavid

Omid Mahdavipour

Ralu Divan

Lara A Gundel

M Tanim Humayun

Augusto Giovanni Gonzalez

Frederick Doering

Qiliang Xu

Dorsa Fahimi

Mehdi Azadmehr

The disclosure provides example mass-sensing instruments and methods for use thereof. A mass-sensing instrument includes a mass sensor that includes a first terminal and a second terminal. The mass sensor has a natural oscillation frequency configured to correspond to a mass of a deposited material on the mass sensor. The mass-sensing instrument also includes a first driving circuit configured to control a first voltage of the first terminal and a second driving circuit configured to control a second voltage of the second terminal.

Mass-sensing instrument with capacitive feedback path

A distally-actuated scanning mirror includes: a mirror block with reflective surface on one side; torsional hinges with proximal ends rigidly attached to the mirror block, and with distal ends attached to flexural structures configured to transform translational motion of the piezoelectric elements into rotational motion of the distal ends of the hinges; and piezoelectric elements providing such translational motion. The distally-actuated scanning mirror also includes flexural structures made of separate flexures attached to the opposite surfaces of the distal ends of the hinges, which flexural structures have defined thinned-down flexural points. Portions of the distally-actuated scanning mirror may be 3D printed and/or fabricated by silicon MEMS technology. The mirror is fabricated from a Silicon-on-Insulator wafer, having a relatively thick (e.g., 380 um) handle layer, and a relatively thin e.g., 50 um), where photolithography with backside-alignment allows separate patterning of these two layers.

Distally actuated scanning mirror

Microfabricated particulate matter (PM) monitors and fractionators within the PM monitors are provided. A primary channel of a vertical or out-of-plane fractionator receives air samples, comprising particles of varying sizes, from the external environment. The air samples then pass through a plurality of microfluidic channels, wherein inertial forces are applied within the microfluidic channels to separate the particles by size. The fractionator comprises a horizontal air outlet for particles having a size below a threshold size and a vertical air outlet for particles having a size above a threshold size. Thus, the proportion of PM in the air sample is reduced prior to deposition on a PM monitor. A virtual cyclone may also be provided that comprises a bend positioned at a flow path through a primary channel of the vertical microfabricated fractionator.

Microfabricated fractionator for particulate matter monitor

Microfabricated PM sensors measure concentrations of particulate matter (PM) in air. Some sensors improve the accuracy of measurements by accounting for the effect of ambient conditions (e.g., temperature or humidity) on mass-sensitive elements employed to determine a mass of the PM in a stream of air. Some sensors improve the accuracy of measurements by controlling humidity in the stream of air measured by mass-sensitive elements. Some sensors employ a plurality of mass-sensitive elements to extend the useful life of the PM sensor. Some sensors employ one or more mass-sensitive elements and heating elements to cause deposition and allow measurement of different sizes of PM. Some sensors can measure mass concentration of coarse PM in addition to fine PM in a stream of air. Some sensors control the flow rate of a stream of air measured by mass-sensitive elements. Some sensors include features to mitigate electromagnetic interference or electromagnetic signal loss.

Particulate matter sensor

Distally-actuated scanning mirror

A method of manufacturing a functionalized pre-treated carbon nanotube. Atomic Layer deposition is utilized to functionalize a pre-treated carbon nanotube. The functionalized pre-treated carbon nanotube may be used in a chemiresistor, including for methane detection.

Pre-treated functionalized multi-walled carbon nanotube based methane sensor

The present disclosure provides for a system and method of concentrating airborne particles, specifically toward the center of one or more intake channels of PM sensors. The invention provides a simple and cost effective device that, when used in conjunction with a MEMS PM sensor or the like, can increase the sensitivity of said device by orders of magnitude. An in-line MEMS PM concentrator uses a converging optical intensity field to concentrate particulate matter along the center of a longitudinal axis of a microchannel. More specifically, the concentrator is designed to bring in ambient air containing PM through a microchannel and concentrate the PM in the center of the microchannel using a converging optical intensity field within a confocal optical cavity.

System and methods of concentrating airborne particles

A method for assessing insulation deterioration in a live underground power cable may include, in one embodiment, attaching a coupling device to a live underground power cable and using the coupling device to couple a test signal onto the power cable. The power cable may carry a normal AC power signal at a first frequency, while the test signal may have a second frequency different from the first frequency. The test signal may be detected after it has traveled a distance along the power cable. It may then be analyzed to determine a change in velocity and/or attenuation of the test signal as a function of the normal AC power signal. The severity of water trees in the power cable may be inferred based on the magnitude of the change.

Method and system for assessing insulation deterioration in live underground power cables

An apparatus for measuring concentrations of airborne particulate matter may include, in one embodiment, a primary channel to receive air samples from the external environment. The air samples include particles of varying sizes. A microfluidic circuit communicates with the primary channel and small particles (having a size less than a threshold size) are diverted around a bend into a secondary channel. Remaining larger particles are unable to make the bend and continue through the primary channel. A mass-sensitive element communicating with the secondary channel includes a collection surface to collect the small particles. A resonant frequency of the mass-sensitive element is reduced in proportion to the mass of the particles collected.

Microfabricated particulate matter monitor

Provided are various embodiments of an adjustment circuit, having a base layer and a piezoelectric layer juxtaposed relative to the base layer and including a first electrode such that when the piezoelectric layer is stressed a polarization charge appears between the base layer and one side of the piezoelectric layer and an opposite polarization charge appears on an opposite side of the piezoelectric layer.

Growing community of inventors

Chicago, IL, United States of America

Igor Paprotny