South Dakota Board of Regents

William Cross

Jon Kellar

Jeevan Meruga

P Stanley May

Aravind Baride

Julian Brackins

David Langerman

John Rapp

Tyler Blumenthal

Dimitrios Anagnostou

Bernado Moreno Baqueiro Sansao

Albert Romkes

An impact test apparatus can be used to determine particle interfacial energies with varying relative air humidity. It was observed that capillary condensation increased the adhesive forces of hydrophilic materials. A systems humidity separation window was identified and the differences in interfacial energy for a hydrophilic surface and for a hydrophobic surface can be exploited in order to achieve the separation of particles. Separation and concentration of particles, particularly particles within a mineral ore body, can be obtained.

Separation of particles of different surface energies through control of humidity

The present invention relates generally to using upconverting inks for producing highly-resolved patterns for inter alia, security applications. More specifically, the present invention relates to the use of sols (inks) and printing processes that produce well-defined printed features consisting of polymers impregnated with luminescent upconversion nanocrystals. The patterns printed using such inks and processes may exhibit defined shapes, characters of text, and various other types of images.

Systems and methods for printing patterns using near infrared upconverting inks

An improved system and method for reading an upconversion response from nanoparticle inks is provided. A is adapted to direct a near-infrared excitation wavelength at a readable indicia, resulting in a near-infrared emission wavelength created by the upconverting nanoparticle inks. A short pass filter may filter the near-infrared excitation wavelength. A camera is in operable communication with the short pass filter and receives the near-infrared emission wavelength of the readable indicia. The system may further include an integrated circuit adapted to receive the near-infrared emission wavelength from the camera and generate a corresponding signal. A readable application may be in operable communication with the integrated circuit. The readable application receives the corresponding signal, manipulates the signal, decodes the signal into an output, and displays and/or stores the output.

Reader apparatus for upconverting nanoparticle ink printed images

The present technology relates generally to a stable oil-in-water emulsion containing upconverting nanoparticles. In particular, the present technology relates to an ink formulation comprising a stable oil-in-water emulsion of upconverting nanoparticles useful for security printing. Preferably the upconverting nanoparticles comprise a &#x3b2;-Na(RE)Fnanoparticle, wherein RE is a lanthanide, yttrium, or a combination or mixture thereof.

Stable oil-in-water nanoemulsion containing upconverting nanoparticles

The present invention relates generally to using upconverting inks for producing highly-resolved patterns for, inter alia, security applications. More specifically, the present invention relates to the use of sols (inks) and printing processes that produce well-defined printed features consisting of polymers impregnated with luminescent upconversion nanocrystals. The patterns printed using such inks and processes may exhibit defined shapes, characters of text, and various other types of images.

An optically scannable code antenna is provided. Encoded matrix codes are printed with electrically conductive material on a substrate. An antenna pattern is generated on the substrate from the electrically conductive material. Enclosed information in the matrix code and accessible via the antenna pattern is provided. At least a portion of the antenna pattern is also a portion of the matrix code. Signals are transmitted and received from the antenna pattern made up of a portion of the matrix code formed on the substrate by electrically conductive materials. Authentication and security measures using the matrix code and signal from the antenna pattern are also provided.

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Rapid City, SD, United States of America

William Cross