Re: Researchers achive real time detection of low gas concentrations

On 13/01/2025 5:15 pm, Jan Panteltje wrote:

Researchers achieve real-time detection of low gas concentrations
  https://www.sciencedaily.com/releases/2025/01/250109125523.htm
   Allowing gas detection and identification in just seconds,
   approach using a coherent control strategy offers promise for
   real-time monitoring in environmental, health and industrial applications
Source:
  Optica
Summary:
Researchers have developed a method for quickly detecting and identifying
  very low concentrations of gases, which, could form the basis for highly
  sensitive real-time sensors for applications such as environmental monitoring,
  breath analysis and chemical process control.
 Interesting method to stop a quartz tuning fork

It's a fairly old-fashioned technique - infra-red spectroscopy has been around for a whole,and if you want to detect low gas concentrations you could always use long-path-length absorbtion cells.
Ring-down detectors are an interesting variant on that approach.
The tuning fork detector may be a novel innovation, but it's less obvious that is a useful one.
"Stopping" a high-Q resonator fast is easy enough, but then you have to wait until the resonant movement builds up again - unless you have one of John Larkin's fast-start resonant devices.
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Bill Sloman, Sydney