Dr. Steven C. Hill Profile

Dr. Steven C. Hill

at CCDC Army Research Lab

SPIE Involvement:

Author

Publications (14)

Proceedings Article | 3 June 2011 Paper

Fluorescence spectra of bioaerosols exposed to ozone in a laboratory reaction chamber to simulate atmospheric processing

Yong-Le Pan, Steven Hill, Ronald Pinnick, Joshua Santarpia, Neal Baker, Benjamin Alvarez, Shanna Ratnesar-Shumate, Brian Cottrell, Laura McKee

Proc. SPIE. 8018, Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) Sensing XII

KEYWORDS: Proteins, Aerosols, Ultraviolet radiation, Particles, Luminescence, Atmospheric physics, Humidity, Ozone, Atmospheric monitoring, Atmospheric particles

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Proceedings Article | 3 October 2008 Paper

Dual-wavelength-excitation single-particle fluorescence spectrometer/particle sorter for real-time measurement of organic carbon and biological aerosols

Yong-Le Pan, Ron Pinnick, Steven Hill, Hermes Huang, Richard Chang

Proc. SPIE. 7116, Optically Based Biological and Chemical Detection for Defence IV

KEYWORDS: Optical filters, Scattering, Sensors, Aerosols, Spectroscopy, Particles, Luminescence, Fluorescence spectroscopy, Laser scattering, Atmospheric particles

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We report the development of a Single-Particle Fluorescence Spectrometer (SPFS) system capable of measuring two UV-laser excited fluorescence spectra from a single particle on-the-fly. The two dispersed fluorescence spectra are obtained from excitation by two lasers at different wavelengths (263 nm and 351 nm). The SPFS samples single particles with sizes primarily in the 1-10 &mgr;m range. The fluorescence spectra are recorded from 280 nm to 600 nm (in 20 channels) for 263 nm excitation and from 370 nm to 700 nm (in 22 channels) for 351 nm excitation. The elastic scattering (channel 4 and 9) is also recorded for sizing each particle. A time stamp for single particles is marked with a variable time interval resolution from 10 ms to 10 minutes. The SPFS employs a virtual-impactor concentrator to concentrate respirable-sized particles with a resulting (size-dependent) effective flow rate of around 100 liters/min. The SPFS can measure single-particle spectra at a maximum rate of 90,000/sec, although the highest rates we have experienced for the ambient are only several hundred/sec. When the SPFS is combined with an aerodynamic deflector (puffer) to sort particles according to their fluorescence spectral characteristics, the SPFS/puffer system can selectively deflect and collect an enriched sample of targeted particles (at rates limited by the puffer) of 1200 particles/sec, for further examination. In laboratory tests, aerosol particles with similar UV-LIF spectra (e.g. B. subtilis and E.coli) are puffed into the reservoir of a micro-fluidic cell, where fluorescent-labeled antibodies bind to them and were classified by their labeled fluorescence. Measurements of the background ambient aerosol with the SPFS system made at sites with different regional climate (Connecticut, Maryland, and New Mexico) were clustered (unstructured hierarchical analysis) into 8-10 groups, with over 90% of all the fluorescent particles contained within these clusters (threshold dot product=0.9). However, the percentage of aerosols in each profile differed by sampling location. The unique features and performance of the SPFS/puffer system compared to other fluorescence-based bio-aerosol sensors will be discussed, with emphasis on reduction of false alarm rates.

Proceedings Article | 8 March 2004 Paper

Two-dimensional angular optical scattering patterns of aerosol particles in the mid-infrared: measurements designed to obtain particle absorption

Kevin Aptowicz, Yong-Le Pan, Ronald Pinnick, Steven Hill, Richard Tober, Richard Chang, Burt Bronk

Proc. SPIE. 5269, Chemical and Biological Point Sensors for Homeland Defense

KEYWORDS: Mid-IR, Refractive index, Scattering, Aerosols, Particles, Light scattering, Laser scattering, Spherical lenses, Atmospheric particles, Absorption

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Proceedings Article | 4 November 2003 Paper

Ultrashort laser applications in lidar and atmospheric sciences

Jerome Kasparian, Riad Bourayou, Veronique Boutou, Catherine Favre, Guillaume Mejean, Didier Mondelain, Andre Mysyrowicz, Miguel Rodriguez, Estelle Salmon, Roland Sauerbrey, Holger Wille, Jean-Pierre Wolf, Ludger Woeste, Jin Yu, L. Klingbeil, K. Rethmeier, W. Kalkner, A. Hartzes, H. Lehman, J. Eisloeffel, Bringfried Stecklum, J. Winkler, Uwe Laux, S. Hoenger, Yong-Le Pan, Richard Chang, Steve Hill

Proc. SPIE. 5226, 12th International School on Quantum Electronics: Laser Physics and Applications

KEYWORDS: Femtosecond phenomena, Atmospheric laser remote sensing, LIDAR, Aerosols, Dispersion, Remote sensing, Laser applications, Atmospheric propagation, Atmospheric sciences, Atmospheric particles

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Proceedings Article | 30 November 1999 Paper

Real-time detection and characterization of individual flowing airborne biological particles: fluorescence spectra and elastic scattering measurements

Yongle Pan, Stephen Holler, Richard Chang, Steven Hill, Ronald Pinnick, Stanley Niles, Jerold Bottiger, Burt Bronk

Proc. SPIE. 3855, Air Monitoring and Detection of Chemical and Biological Agents II

KEYWORDS: Mirrors, Scattering, Aerosols, Particles, Luminescence, Laser scattering, Semiconductor lasers, Scatter measurement, Atmospheric particles, Bacteria

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Proceedings Article | 18 January 1999 Paper

Two-dimensional angular scattering measurements of single airborne microparticles

Stephen Holler, Yongle Pan, Jerold Bottiger, Steven Hill, David Hillis, Richard Chang

Proc. SPIE. 3533, Air Monitoring and Detection of Chemical and Biological Agents

KEYWORDS: Optical spheres, Scattering, Cameras, Particles, Luminescence, Light scattering, Laser scattering, Bioalcohols, Scatter measurement, Atmospheric particles

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Proceedings Article | 18 January 1999 Paper

Concentration, size, and excitation power effects on fluorescence from microdroplets and microparticles containing tryptophan and bacteria

Nicholas Fell, Ronald Pinnick, Steven Hill, Gorden Videen, Stanley Niles, Richard Chang, Stephen Holler, Yongle Pan, Jerold Bottiger, Burt Bronk

Proc. SPIE. 3533, Air Monitoring and Detection of Chemical and Biological Agents

KEYWORDS: Cameras, Ultraviolet radiation, Particles, Luminescence, Reflectivity, Objectives, Zoom lenses, Analytical research, Atmospheric particles, Bacteria

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Proceedings Article | 26 September 1997 Paper

Green function for fluorescence from spherical particles located on a substrate

Gorden Videen, Steven Hill, J. Pendleton

Proc. SPIE. 3141, Scattering and Surface Roughness

KEYWORDS: Optical spheres, Scattering, Particles, Luminescence, Interfaces, Silicon, Raman spectroscopy, Spherical lenses, Semiconducting wafers, Atmospheric particles

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Proceedings Article | 30 May 1997 Paper

Aerosol fluorescence spectrum analyzer for individual airborne biological particles

Gang Chen, Ronald Pinnick, Steven Hill, Richard Chang, Paul Nachman, Gorden Videen

Proc. SPIE. 3105, Chemical, Biochemical and Environmental Fiber Sensors IX

KEYWORDS: Scattering, Aerosols, Ultraviolet radiation, Particles, Luminescence, Laser scattering, Laser beam diagnostics, Signal detection, Atmospheric particles, Bacteria

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Proceedings Article | 15 September 1993 Paper

Linear and nonlinear scattering by a dielectric sphere

Dipakbin Chowdhury, Md. Mohiuddin Mazumder, Steven Hill

Proc. SPIE. 1968, Atmospheric Propagation and Remote Sensing II

KEYWORDS: Refractive index, Optical spheres, Scattering, Aerosols, Remote sensing, Laser scattering, Spherical lenses, Atmospheric propagation, Atmospheric particles, Absorption

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Proceedings Article | 24 May 1993 Paper

Light scattering by radially inhomogeneous fuel droplets in a high-temperature environment

Michael Schneider, E. Dan Hirleman, Hasan Saleheen, Dipakbin Chowdhury, Steven Hill

Proc. SPIE. 1862, Laser Applications in Combustion and Combustion Diagnostics

KEYWORDS: Refractive index, Optical spheres, Polarization, Scattering, Diffusion, Light scattering, Ray tracing, Palladium, Geometrical optics, Liquids

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Proceedings Article | 24 May 1993 Paper

Modeling nonlinear optical mixing processes in droplets

Steven Hill, Richard Chang

Proc. SPIE. 1862, Laser Applications in Combustion and Combustion Diagnostics

KEYWORDS: Second-harmonic generation, Optical spheres, Polarization, Chemical species, Interfaces, Combustion, Raman spectroscopy, Sum-frequency generation, Dielectric polarization, Liquids

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