Complexes of Cut (II), Ni(II) & Co(II) with 3,5-Dimethyl-I-nitroguanylpyrazole

978-98

Numerical Study About the Change in Flow Separation and Velocity Distribution in a 90° Pipe Bend with/without Guide Vane Conditions

A single phase, incompressible turbulent flow through a 90º pipe bend with/without guide vane conditions has been studied here. The present work deals with the numerical simulation to investigate the change in flow separation and velocity distribution at the downstream section due to the effect of the guide vane.  The k-? turbulence model has been adopted for simulation purposes to obtain the results. After the validation of existing experimental and numerical results, a detailed study has been performed for three different Reynolds number and four different positions of the guide vane. The value of the Curvature ratio (Rc/D) has been considered as one factor for the present study. The curvature ratio can be defined as the ratio between the bend curvature radius and hydraulic diameter of the pipe. The results obtained from the present study have been presented in graphical form. A flow separation region has been found at the bend outlet for flow through 90º pipe bend without the guide vane. This flow separation region was absent for the cases which dealt with the flow through 90º pipe bend with the guide vane. Velocity distribution at four different downstream positions for different cases and different Reynolds numbers have been compared and reported in the present study

Understanding micro-image configurations in quasar microlensing

The micro-arcsecond scale structure of the seemingly point-like images in lensed quasars, though unobservable, is nevertheless much studied theoretically, because it affects the observable (or macro) brightness, and through that provides clues to substructure in both source and lens. A curious feature is that, while an observable macro-image is made up of a very large number of micro-images, the macro flux is dominated by a few micro-images. Micro minima play a key role, and the well-known broad distribution of macro magnification can be decomposed into narrower distributions with 0,1,2,3,... micro minima. This paper shows how the dominant micro-images exist alongside the others, using the ideas of Fermat's principle and arrival-time surfaces, alongside simulations.Comment: Accepted for publication in MNRA

Radial density profiles of time-delay lensing galaxies

We present non-parametric radial mass profiles for ten QSO strong lensing galaxies. Five of the galaxies have profiles close to $\rho(r)\propto r^{-2}$, while the rest are closer to r^{-1}, consistent with an NFW profile. The former are all relatively isolated early-types and dominated by their stellar light. The latter --though the modeling code did not know this-- are either in clusters, or have very high mass-to-light, suggesting dark-matter dominant lenses (one is a actually pair of merging galaxies). The same models give H_0^{-1} = 15.2_{-1.7}^{+2.5}\Gyr (H_0 = 64_{-9}^{+8} \legacy), consistent with a previous determination. When tested on simulated lenses taken from a cosmological hydrodynamical simulation, our modeling pipeline recovers both H_0 and $\rho(r)$ within estimated uncertainties. Our result is contrary to some recent claims that lensing time delays imply either a low H_0 or galaxy profiles much steeper than r^{-2}. We diagnose these claims as resulting from an invalid modeling approximation: that small deviations from a power-law profile have a small effect on lensing time-delays. In fact, as we show using using both perturbation theory and numerical computation from a galaxy-formation simulation, a first-order perturbation of an isothermal lens can produce a zeroth-order change in the time delays.Comment: Replaced with final version accepted for publication in ApJ; very minor changes to text; high resolution figures may be obtained at justinread.ne

Time-delay quasars: scales and orders of magnitudes

We can think of a lensed quasar as taking the Hubble time, shrinking it by \~10^{-11}, and then presenting the result to us as a time delay; the shrinking factor is of the order of fractional sky-area that the lens occupies. This cute fact is a straightforward consequence of lensing theory, and enables a simple rescaling of time delays. Observed time delays have a 40-fold range, but after rescaling the range reduces to 5-fold. The latter range depends on details of the lens and lensing configuration--for example, quads have systematically shorter rescaled time delays than doubles--and is as expected from a simple model. The hypothesis that observed time-delay lenses all come from a generalized-isothermal family can be ruled out. But there is no indication of drastically different populations either.Comment: To appear in A&

Cobalt(II), Nickel(II) & Copper(II) Complexes of N-Benzylidene-5(3)-methylpyrazole-3(5)-carbohydrazide Schiff Base

203-20

Bis-chelate Complexes of Co(II) with ɑ-(3,5-Dimethyl-l- pyrazolyl )acetohydrazide

812-81

Monochelate Complexes of Copper(II) with ɑ-(3,5-Dimethyl-1-pyrazolyl)acetohydrazide

154-15

Complexes of Cobalt(II), Nickel(II) & Copper(II) with ɑ -(3,5-Dimethyl-1-pyrazolyl)acetamide

574-57

Chelating Properties of A New Pyrazole-based ONS Tridentate Ligand: Cobalt(II) & Nickel(II) Complexes with 5-Methyl-I-thiocarbamyl-pyrazole-3-carboxylic Acid

680-68