We present the final results from a high sampling rate, multi-month, spectrophotometric reverberation mapping campaign undertaken to obtain either new or improved Hβ reverberation lag measurements for several relatively low-luminosity active galactic nuclei (AGNs). We have reliably measured the time delay between variations in the continuum and Hβ emission line in six local Seyfert 1 galaxies. These measurements are used to calculate the mass of the supermassive black hole at the center of each of these AGNs. We place our results in context to the most current calibration of the broad-line region (BLR) R BLR -L relationship, where our results remove outliers and reduce the scatter at the low-luminosity end of this relationship. We also present velocity-resolved Hβ time-delay measurements for our complete sample, though the clearest velocity-resolved kinematic signatures have already been published.

A detailed analysis of the data from a high sampling rate, multi-month reverberation mapping campaign, undertaken primarily at MDM Observatory with supporting observations from telescopes around the world, reveals that the Hβ emission region within the broad line regions (BLRs) of several nearby AGNs exhibit a variety of kinematic behaviors. While the primary goal of this campaign was to obtain either new or improved Hβ reverberation lag measurements for several relatively low luminosity AGNs, we were also able to unambiguously reconstruct velocity-resolved reverberation signals from a subset of our targets. Through high cadence spectroscopic monitoring of the optical continuum and broad Hβ emission line variations observed in the nuclear regions of NGC 3227, NGC 3516, and NGC 5548, we clearly see evidence for outflowing, infalling, and virialized BLR gas motions, respectively.

We present the first results from a high sampling rate, multi-month reverberation mapping campaign undertaken primarily at MDM Observatory with

Novel water-soluble biodegradable polyphosphazenes are described. Polymers are constructed on the basis of a biodegradable polyphosphazene backbone to mimic the structure of poly(vinylpyrrolidone), PVP. Poly{di[2-(2-oxo-1-pyrrolidinyl)ethoxy]phosphazene}, PYRP, and its copolymers containing biologically active carboxylatophenoxy side groups have been synthesized. The ability of these polymers to degrade in aqueous environment at 37°C is demonstrated by light scattering-GPC and NMR studies. The degradation is manifested by the gradual decrease in the molecular weight and release of the side group -1-(2-hydroxyethyl)-2-pyrrolidone. It has been shown that the incorporation of N-ethylpyrrolidone containing side groups in the polymer structure can modulate degradation profiles of phosphazene copolymers. The kinetics of hydrolytic degradation and the effect of pH on the degradation rate have been investigated.

Polyphosphazene polyelectrolytes containing various amounts of hydrophobic fluorinated moieties and ionic carboxylic acid groups were synthesized. Polymer compositions and molecular weights were characterized by NMR and gel permeation chromatography. Interestingly, poly[(carboxylatophenoxy)(trifluoroethoxy)phosphazene] containing 60 mol % fluorinated groups was found to be soluble in aqueous solutions. The behavior of fluorinated polyelectrolytes in reactions of ionic complexation with multivalent and monovalent salts was studied in aqueous solutions and ethanolwater mixtures. Such reactions led to the formation of ionotropic hydrogels under mild conditions and, thus, are of importance to the development of microencapsulation processes and controlled release formulations. All of the synthesized polymers underwent phase separation in the presence of multivalent ionic crosslinkers, such as spermine and calcium chloride. This included a water-soluble polyelectrolyte containing 40 mol % ionic groups and hydrophobic polymer with only 3 mol % carboxylic acid groups.