Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Detecting Chemical Threats With "Intelligent" Networks

11.09.2003


Micrograph of NIST sensor device used to detect toxic gases. Colors reflect slight variations in thickness of the sensing film.


Prototype microsensor arrays connected to artificial neural networks—computer models that “learn”—can reliably identify trace amounts of toxic gases in seconds, well before concentration levels become lethal, National Institute of Standards and Technology (NIST) scientists and a guest researcher reported Sept. 7 at the American Chemical Society annual meeting in New York City. The system has the potential to provide cost-effective early warning of chemical warfare agents.

Lab experiments show that the sensors, which use NIST-patented microheater technology, can detect compounds such as sulfur-mustard gas and nerve agents (tabun and sarin) at levels below 1 part per million. The neural networks, which currently run on a personal computer, were added recently to process signals from the sensor arrays. The networks enable the system to rapidly distinguish among the gases and predict their concentration in the ambient air.

The microheaters, which are coated with metal oxide films, can be programmed to cycle through a range of temperatures. Airborne chemicals attach to the film in characteristic ways depending on factors such as temperature and film material, causing changes in the flow of electricity through the microsensors. These changes serve as a “signature” for identifying both the type and concentration of the gas in the ambient air.



The neural networks were trained to detect subtle variations in these signatures. An array of four microheater sensors programmed to quickly sample 20 temperatures produces as much data as 80 different sensors.

Research is ongoing to more fully assess the impact of background interference as a means of avoiding false positives, and to enhance the robustness of the sensors with repeated use. The research is funded by NIST and the Defense Threat Reduction Agency.

Media Contact:
Laura Ost, (301) 975-4034

Laura Ost | NIST
Further information:
http://www.nist.gov/public_affairs/techbeat/tb2003_0910.htm

More articles from Information Technology:

nachricht Construction of practical quantum computers radically simplified
05.12.2016 | University of Sussex

nachricht UT professor develops algorithm to improve online mapping of disaster areas
29.11.2016 | University of Tennessee at Knoxville

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Closing the carbon loop

08.12.2016 | Life Sciences

Applicability of dynamic facilitation theory to binary hard disk systems

08.12.2016 | Physics and Astronomy

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D

08.12.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>