12-04 :: April/May 2012

nanotimes News in Brief

At the Analytica trade fair in Germany, Fraunhofer researchers, joined by the Hübner Company, are presenting a terahertz spectrometer that provides reliable, contact-free identification of substances. At the end of 2011, though, the scanner T-Cognition 1.0 from Hübner company of Kassel, Germany, went on the market. The device, developed with the assistance of Fraunhofer researchers, detects, without contact, substances such as drugs or explo- sives contained in unopened letters or flat packages

“You place the suspicious parcels or letters in a kind of drawer, and the device uses terahertz waves to determine whether it contains explosives. This protects confidentiality, and the mail can then be delivered safely,” explains Dr. Joachim Jonuscheit, deputy division director at Fraunhofer Institute for Physical Measurement Techniques IPM and the researcher in charge of terahertz analysis there. The attacks in Rome and Frankfurt fueled the security industry‘s interest in the analysis device.

“Most dielectric materials, such as plastics, clothing or paper, are transparent to microwaves and can also be penetrated by terahertz waves with compa- ratively low reduction. For non-destructive non- destructive testing, the terahertz range is extremely interesting,” the expert adds. On the electroma- gnetic spectrum, terahertz waves can be found at the junction between microwaves and infrared radiation. The frequency range extends from 100 GHz to 10 THz; this corresponds to a wavelength from 3mm to 30µm. Terahertz waves combine the benefits of the adjoining spectral ranges: high penetration depth and low scatter, accompanied by good spatial resolution and the capability of spectral identification of unknown substances.

Fraunhofer Institute for Physical Measurement Techniques IPM: http://www.ipm.fraunhofer.de

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A team of Michigan Technological University (US) materials scientists developed a comparably foolproof method for creating sheets of titanium dioxide embedded with graphene. It first made gra- phite oxide powder, then mixed it with titanium di- oxide to form a paste, spread it on a substrate (such as glass) and then baked it a high temperatures.