Pendar authors are working on cutting edge research, every day. Read on for some highlights of our published results.
We present a gas sensing system based on quartz-enhanced photoacoustic spectroscopy (QEPAS) employing a monolithic distributed-feedback quantum cascade laser (QCL) array operated in a pulsed mode as a light source. A detection sensitivity of less than 60 parts-per-billion was achieved permitting the monitoring of nitrous oxide at global atmospheric levels.[Reprint]
An investigational device based on resonance Raman spectroscopy (RRS) can assess in real time whether the body’s tissues are receiving enough oxygen, report researchers from Pendar Technologies and Boston Children’s Hospital. The study, conducted in animal models, is the cover article in the September 20, 2017 issue of Science Translational Medicine. The authors demonstrated that a new measure of mitochondrial redox state, which they named resonance Raman reduced mitochondrial ratio, or 3RMR, could predict impending cardiac arrest in an animal model of hypoxia or ischemia. The study demonstrates the application of resonance Raman spectroscopy in the complex peri-operative environment of the beating, blood perfused heart. [Abstract] [Reprint] [Full Text]
This article presents new spectroscopic results in standoff chemical detection that are enabled by monolithic arrays of Distributed Feedback (DFB) Quantum Cascade Lasers (QCLs), with each array element at a slightly different wavelength than its neighbor. Experimental standoff detection results using the man-portable system for droplet examination from 1.3 meters are presented using the CWAs VX and T-mustard as test cases. [Reprint]
Advances in infrared (IR) laser sources, optics, and detectors promise major new advances in areas of chemical analysis such as trace-gas monitoring, IR microscopy, industrial safety, and security. One key type of photonic device that has yet to reach its full potential is a truly portable noncontact (stand-off), chemically versatile analyzer for fast Fourier-transform infrared (FTIR)-quality spectral examination of nearly any condensed-phase material. Laser Focus World
Methane is a powerful greenhouse gas that has both natural and anthropogenic sources. The ability to measure methane using an integrated path length approach such as an open/long-path length sensor would be beneficial in several environments for examining anthropogenic and natural sources, including tundra landscapes, rivers, lakes, landfills, estuaries, fracking sites, pipelines, and agricultural sites. Here a broadband monolithic distributed feedback-quantum cascade laser array was utilized as the source for an open-path methane sensor. Two telescopes were utilized for the launch (laser source) and receiver (detector) in a bistatic configuration for methane sensing across a 50 m path length. Direct-absorption spectroscopy was utilized with intrapulse tuning. Ambient methane levels were detectable, and an instrument precision of 70 ppb with 100 s averaging and 90 ppb with 10 s averaging was achieved. The sensor system was designed to work “off the grid” and utilizes batteries that are rechargeable with solar panels and wind turbines. Learn More