Verification and Validation of NASA-Supported Enhancements to the Near Real Time Harmful Algal Blooms Observing System (HABSOS)

This report discusses verification and validation (V&V) assessment of Moderate Resolution Imaging Spectroradiometer (MODIS) ocean data products contributed by the Naval Research Laboratory (NRL) and Applied Coherent Technologies (ACT) Corporation to National Oceanic Atmospheric Administration s (NOAA) Near Real Time (NRT) Harmful Algal Blooms Observing System (HABSOS). HABSOS is a maturing decision support tool (DST) used by NOAA and its partners involved with coastal and public health management

Investigation of the bank texture occurring in hydroxypropylcellulose solutions using rheo-optical, rheological and small angle light scattering techniques

The band texture occurs in lyotropic and thermotropic main-chain polymers after cessation of flow. This paper begins with a review of work concerned with band texture formation following shear and is followed by the presentation of original results obtained during a recent investigation. The evolution of band texture formation in a Klucel EF, 50% hydroxypropylcellulose (HPC) water solution, has been observed using polarized optical microscopy. The relationship determined between the primary shear rate and the rate of evolution of the band texture is complex and three different behaviours have been observed corresponding to three shear rate regions. Both steady flow and dynamic rheological investigations have been conducted on the HPC solution, the results of which have been related to the optical behaviour of the band texture. Data from steady flow investigations suggest that the viscosity of the solution when the band texture is present, decreases following increasing primary shear rates, is shear thinning and increases linearly with the time following its formation. Dynamic investigations suggest a definite link between the band texture evolution and the evolution of both G′ and G′′. In addition, the perfection of the band texture versus the primary shear rate has been quantified by studying the evolution of tan(δ) following the cessation of the primary shear. Dynamic experiments show that the structure of the band texture remains longer than suggested by the optical aspect of the texture. Small angle light scattering patterns have been correlated with the development of the band texture and confirm the continuing presence of the band texture structure following its optical disappearance

A Light Scattering Theory for Filled Diluted Polymer Solution under Flow

Light scattering by dilute flexible polymer solutions filled with spherical particles is studied theoretically within the framework of the Rayleigh-Gans-Debye approximation. The basic idea of our work is that the perturbation of stream lines and flow rates due to the presence of the particles will change the local conformation of the chains, thus inducing a light scattering contribution. This treated by considering viscosity fluctuations. The Rayleigh ratio is derived as a function of the viscosity fluctuation correlation function for the four major polarization configurations (HH, VV, HV and VH) in shear and elongational flow. Considering a random distribution of the particles, the small angle light scattering patterns are calculated.La diffusion de lumière par des solutions de polymères flexibles chargées de particules sphériques est étudiée grâce à l'approximation théorique de Rayleigh-Gans-Debye. L'idée de base du travail est que les perturbations des lignes de courant et des taux d'écoulement dues à la présence des particules vont changer la conformation locale des chaines, entrainant une diffusion de la lumière. Traitant ces perturbations comme des fluctuations de viscosité, le rapport de Rayleigh est calculé en tenant compte de la fonction de corrélation des fluctuations de viscosité pour les quatres orientations principales des polariseurs, HH, VV, HV et VH, et pour des écoulements de cisaillement et d'élongation. Les clichés de diffusion de lumière sont calculés en considérant une distribution aléatoire de particules