High fluences inside cavity ring-down spectroscopy optical resonators lend themselves to fluorescence or Raman spectroscopy. An instrument at 488 nm was developed to measure extinction, and fluorescence of aerosols. A detection limit of 6 x 10;-9 cm;-1Hz;-1/2 (0.6 Mm;-1Hz;-1/2) was achieved. The fluorescence spectral power collected from a single fluorescent microsphere was 10 to 20 pW/nm. This...

We report the first laser-induced fluorescence ~LIF! excitation spectrum of the ketenyl radical, HCCO, which is produced by the 193 nm photolysis of ketene in a free jet expansion. A series of vibronic bands in the B̃ P– X̃ A9 system are observed. The LIF band positions and rotational structures are in excellent agreement with those of a recent photofragment yield ~PFY! spectrum @D. L. Osborn et ...

The secondary and tertiary structure of human plasma thyroxine-binding globulin (TBG) was investigated by circular dichroism and fluorescence properties. The relaxation time of TBG indicated that it is a compact, symmetric molecule. It was calculated from the far ultraviolet CD spectrum that about one-half of the peptide groups are equally distributed in alpha helical and beta structures. In th...

We present the use of correlation analysis on spectral data in order to quantify the amount of a given spectrum present with respect to a reference spectrum. The method is shown to be useful in analyzing hyperspectral fluorescence images. It is unhindered by the linear relationship assumed in linear spectral unmixing, and in addition, it is shown to be robust with respect to noise.

A real-time three dimensional (3D) fluorescence imaging system incorporating wavelength-coded and multiplexed holographic gratings is presented. Holographic gratings formed in thick Phenanthrenquinone(PQ-) Doped Poly (methyl methacrylate) (PMMA) have narrowband spectral-spatial transmittance filtering properties to generate wavelengthspectrum selective multi-focal planes within a biological obj...

Fluorescence spectroscopy was used to characterize blue light responses from chloroplasts of adaxial guard cells from Pima cotton (Gossypium barbadense) and coleoptile tips from corn (Zea mays). The chloroplast response to blue light was quantified by measurements of the blue light-induced enhancement of a red light-stimulated quenching of chlorophyll a fluorescence. In adaxial (upper) guard ce...

This work presents a promising method for automatic non-contact detection and counting of salmon lice infested on in an aquacultural farm setting. The uses fluorescence the visual part spectrum to enhance contrast between fish skin lice. wavelengths used are compatible with underwater measurement system.