Fourier horn

The technology and the science of a device for pulmonary drug delivery have been described (35). The core of this device is a centimeter-size, clog-free silicon-based ultrasonic nozzle with multiple Fourier horns in resonance at a frequency in the MHz range. 

F. W. McLafferty, D. M. Horn, K. Breuker, Y. Ge, M. A. Lewis, B. Cerda, R. A. Zubarev, and B. K. Carpenter, Electron capture dissociation of gaseous multiply charged ions by Fourier-transform ion cyclotron resonance, J. Am. Soc. Mass Spectrom., 12 (2001) 245-249. 

Figure 1 Diagram of the chirped-pulse, Fourier transform microwave spectrometer showing the generation of the the linear frequency sweep which is bandwidth multiplied and amplified. The inset shows the pulse in both time and frequency space. The pulse is broadcast into the chamber through a double-ridge microwave horn and the free induction decay (FID) is collected with another microwave horn. The FID is downconverted to the 0.5 - 11.5 GFIz range before being recorded by the oscilloscope.

Breuker, K. Oh, H. Cerda, B. Horn, D.M. McLafferty, F.W. Hydrogen atom loss in ECD A Fourier transform ion cyclotron resonance study with single isotopomeric ions. Eur. J. Mass Spectrom. 2002, 8, 177-180. 

Cl. A. Brock, D. M. Horn, E. C. Peters, C. M. Shaw, C. Eiricson, Q. T. Fung, and A. R. Salomon, An automated matrix-assisted laser desorption/ionization quadrupole-Fourier-transform ion cyclotron resonance mass spectrometer. Anal. Chem. 75, 3419-3428 (2003). 

Schaub, T. M., Hendrickson, C. L., Horning, S., Quinn, J. P., Senko, M. W., Marshall, A. G. (2008) High-performance mass spectrometry Fourier transform ion cyclotron resonance at 14.5 tesla. Anal Chem, 80, 3985-3990. 

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