High resolution images of P/Tempel 1 and P/Tempel 2 constructed from IRAS survey data

Infrared images of P/Tempel 1 and P/Tempel 2 were constructed from IRAS survey data using a computer algorithm based on the Maximum Correlation Method for Image Construction (Aumann et al, 1990). The resulting images are of sufficiently high quality and resolution to delineate coma and tail morphology, and permit accurate photometry of the total dust complex. Comparisons of the infrared colors and photometric profiles of Tempel 1 and Tempel 2 at similar heliocentric distances show that the grains produced by the two comets are quite similar in radiometric and dynamic properties. Tempel 1 is found to produce about 30 percent more dust in its coma and tail than Tempel 2. The comae of Tempel 1 and Tempel 2 are expanding with mean velocities of 5.8 plus or minus 0.07 and 6.1 plus or minus 0.17 m/sec respectively, indicative of the ejection of large grains. The IRAS cataloged infrared fluxes (Walker, 1986) are found to be underestimated by as much as a factor of three for the comets. Therefore, it is essential to create images of the comets to obtain meaningful IRAS photometry

\u3ci\u3eIxodes Dentatus\u3c/i\u3e (Acari: Ixodidae) in Michigan: First State Records and Occurrence on a Human

An Ixodes dentatus adult female was taken from a cottontail rabbit in Kalamazoo County, and a nymph from a child in Berrien County, in 1992 in Michigan. These findings represent the first records of I.dentatus in the state, and document an unusual parasitization of a human being by this species of tick

NMR studies of catalysts: phosphorous-31 and vanadium-51 in vanadium-phosphorous-oxygen selective oxidation catalysts and the selective averaging of the second order quadrupolar interaction in aluminosilicates

The results of EPR and (\u2731)P and (\u2751)V NMR experiments on vanadium-phosphorous-oxygen catalysts revealed the presence of V(III) as well as the expected V(IV) and V(V). Preparations known to be highly oxidized, such as (beta)-VOPO(,4) and B phase catalyst with P/V = 0.9, yielded NMR spectra showing only small effects of unpaired electron spin, and the EPR spin count indicated a correspondingly low concentration of V(IV). On the other hand, catalysts known to be highly reduced, such as butane-treated (VO)(,2)P(,2)O(,7) and B phase catalysts with P/V = 1.0, 1.1, gave NMR spectra with strong effects of unpaired electron spin but low EPR spin counts. Since EPR will routinely detect V(IV) but not V(III) (and no unpaired electron spins are associated with V(V)), the strong paramagnetic effects observed in the reduced catalysts must result from V(III). The catalysts examined included the model compounds (beta)-VOPO(,4) and (VO)(,2)P(,2)O(,7) before and after butane and butane treatment, precatalysts (P/V = 0.9, 1.0, 1.1) and B phase catalysts (P/V = 0.9, 1.0, 1.1) before and after butane treatment;The line broadening effects of the second order quadrupolar interaction cause loss of resolution in the NMR spectra of interesting systems, such as (\u2727)Al in zeolites. A multiple pulse sequence proposed to selectively average the effects of the second order quadrupolar interaction was investigated. The negative results obtained, including an echo of problematic origin, are described

The Feasibility of Trophic Manipulation in Grayson Lake, Kentucky, U.S.A.

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Masters of Science by Russell Walker Crawford on July 19, 1995

The effect of the quasar H1821+643 on the surrounding intracluster medium: revealing the underlying cooling flow

We present a detailed study of the thermodynamic properties of the intracluster medium of the only low redshift galaxy cluster to contain a highly luminous quasar, H1821+643. The cluster is a highly massive, strong cool core cluster. We find that the ICM entropy around the quasar is significantly lower than that of other similarly massive strong cool core clusters within the central 80 kpc, and that the entropy lies significantly below the extrapolated baseline entropy profile from hierarchical structure formation. By comparing the scaled temperature profile with those of other strong cool core clusters of similar total mass, we see that the entropy deficiency is due to the central temperature being significantly lower. This suggests that the presence of the quasar in the core of H1821+643 has had a dramatic cooling effect on the intracluster medium around it. We find that, if the quasar was brighter in the past, Compton cooling by radiation from the quasar may have caused the low entropy and temperature levels in the ICM around the quasar. Curiously, the gradients of the steep central temperature and entropy decline are in reasonable agreement with the profiles expected for a constant pressure cooling flow. It is possible that the system has been locked into a Compton cooled feedback cycle which prevents energy release from the black hole heating the gas sufficiently to switch it off, leading to the formation of a huge (~3x10^10 solar mass) supermassive black hole.Comment: 8 pages, 10 figures. Accepted for publication in MNRA