Publications by authors named "Benjamin W Smith"

The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader perspective can be provided partially by general overviews but then the thinking, experimental details, theoretical underpinnings and instrumental innovations of the original work must be sacrificed.

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This work reports an investigation on the feasibility of using a photomultiplier tube (PMT) to follow the time evolution of self-absorption of copper resonance transitions at 324.7 nm and 327.4 nm.

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In this study, we present an experimental investigation of the parameters of the laser spark ignition of premixed methane-air mixtures and the determination of the key factors for the ultimate ignition result. Ignition is achieved in a mesh honeycomb burner using the 1064 nm output of a neodymium-doped yttrium aluminum garnet (Nd : YAG) laser. All pertinent laser ignition parameters, including the minimum ignition energy, the ignition time and blow out time, and the effects that the variation of experimental conditions, such as the spark energy, ignition position, equivalence ratio (ER), and flow rate, have on these parameters have been addressed systematically.

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A simple, fast, reliable, sensitive and potentially portable explosive detection device was developed employing laser photofragmentation (PF) followed by heterogeneous chemiluminescence (CL) detection. The PF process involves the release of NO(x(x = 1,2)) moieties from explosive compounds such as TNT, RDX, and PETN through a stepwise excitation-dissociation process using a 193 nm ArF laser. The NO(x(x = 1,2)) produced upon PF is subsequently detected by its CL reaction with basic luminol solution.

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Real-time characterization of the chemical and physical properties of individual aerosol particles is an important issue in environmental studies. A well-established way of accomplishing this task relies on the use of laser-induced fluorescence or laser ionization mass spectrometry. We describe here a simple approach aimed at experimentally verifying that single particles are indeed addressed.

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Cavity ring-down spectroscopy was explored as a means to measure atmospheric optical extinction. Ambient air was sampled through a window on the campus of the University of Florida and transported to a ring-down cell fashioned from standard stainless steel vacuum components. When a copper vapor laser operating at 10 kHz is employed, this arrangement allowed for nearly continuous monitoring of atmospheric extinction at 510 and 578 nm.

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