Continuous-wave cavity ring-down spectroscopy uses the behavior of laser light passed through a gas sample to provide fast and accurate measurements of contaminants down to parts per trillion (ppt) levels.

Last month we discussed how IMS and DMS are used for trace chemical detection. Now we consider how the two technologies can be used in tandem to achieve greater selectivity and sensitivity and fewer false positives.

The first installment of this two-part series discusses ion mobility spectroscopy (IMS), the leading contender for fast and reliable detection of trace chemicals, and differential ion mobility spectroscopy (DMS), a related technology that provides faster, smaller and more sensitive sensors capable of detecting chemicals in environments with greater concentrations of interfering substances.

Knowing the viscosity of an oil allows you to determine its condition; we evaluate a real-time viscosity sensor and compare its results with those generated using a lab rheometer.

By keeping tabs on your equipment's lubricating fluids, you can prolong the operating life of your machinery and reduce the cost of ownership.

Better Security with Ambient Air Sensing Dec 1, 2006 By: John S. Kauer, Barbara Talamo

We all want to feel safe in public places, and knowing that there's nothing noxious in the air is a strong step in that direction.

The demand for sensitive, low-power, low-cost gas sensors that respond quickly to appropriate stimuli is growing. Macro scale components and conventional manufacturing techniques cannot provide sensors that deliver the detection levels and low-power operation increasingly required by today's applications. And many of these sensors are prone to false alarms. However, manipulating sensing events at the molecular level avoids most problems associated with the more traditional sensor technologies.

Ethanol pH = Mean Beer May 1, 2006 By: Stephanie vL Henkel

Archer Daniels Midland Co. (ADM) makes ingredients for human food and animal feed, as well as renewable fuels and naturally derived alternatives to industrial chemicals. In 1971, ADM acquired Corn Sweeteners Inc., Cedar Rapids, Iowa, which it subsequently expanded into ethanol production.

Operating on the scale of atoms and molecules, emerging nanotechnologies promise dramatic changes in sensor designs and capabilities.