Chemistry of the Spring Waters of the Ouachita Mountains Excluding Hot Springs, Arkansas

This report is based on the chemical analysis of the waters from 93 springs and 9 wells. Springs, when free from metal plumbing, provide an uncontaminated source of the ground water and it was desired to obtain water uncontaminated with metals. A few wells were added to the list, usually because of their unique location in the sampling grid

Nutrients and Acid in the Rain and Dry Fallout at Fayetteville, Arkansas (1980-1982)

Wet and dry fallout at Fayetteville, Arkansas have been collected separately and analyzed since April, 1980. The precipitation-weighted-average pH for two yearly periods of rainfall were 4.72 (6/80-5/81) and 4.75 (6/81-5/82). This corresponds to a concentration of the acid ion, H+, of about 18 parts per billion (ppb). Pure water in equilibrium with the CO2 of the air would have a pH of 5.65 (2.2 ppb of H+). The range of pH during this two year period was 3.86-7.74(140-0 ppb H+) for the rainfall. Aqueous extracts of the dry fallout were always in the 6.75-7.87 pH range, i.e., neutral to slightly alkaline. The slight amount of acidity in the Fayetteville rainfall should be easily neutralized by dry fallout and soil. Ammonium bisulfate, NH4HSO4, is the major acidic chemical in the rains. Sulfur tends to increase in winter months presumably due to the greater use of fossil fuels. Northern rains have the most acidity. Wet and dry fallout add significant amounts of nutrients to the local soils with 25-87% of the total flux being dry fallout. A. major contributor are dust storms which bring in soil from adjacent states. Iron and zinc were the most prevalent heavy metals in the wet fallout. Their concentrations were very low averaging less than 10 ppb for Fe and 15 ppb for Zn. Northernly and southernly rains had the most Fe and Zn and correspond to directions in which there are smelters

\u3ci\u3eMicroctonus Pachylobii\u3c/i\u3e (Hymenoptera: Braconidae): New Host Record From \u3ci\u3eHylobius Radicis\u3c/i\u3e (Coleoptera: Curculionidae), and Additional Notes on Its Biology

The endoparasite Microctonus pachylobii was discovered parasitizing a new weevil host, Hylobius radicis. Thirteen of the 154 H. radicis adults collected were parasitized (8.5%). The median numbers of parasites per weevil were 26 (x =22.5) during the period April through June, and 4 (x =9.4) during August and September. The median male:female sex ratio was 0.91 (x =0.65). Males emerged approximately 1 day earlier than females. Median parasite mortality while in the cocoon was 10.2% per parasitized weevil (x = 11.8%). Microctonus pachylobii was not found parasitizing two previously recorded weevil hosts from field samples, Hylobius rhizophagus and H. pales, and a laboratory study suggests that the parasite may have difficulty parasitizing the latter species

A search for periodicity in the x ray spectrum of black hole candidate A0620-00

The archived data from the SAS-3 observations of the X-ray nova A0620-00, the best of the stellar blackhole candidates, were exhaustively examined for evidence of variable phenomena correlated with the orbital motion of the binary system of which it is a member. The original analysis of these data was completed before discovery of the binary companion and determination of the orbital period of the system. New interest was drawn to the task of a reexamination of the archive data by the recent discovery of the massive nature of the X-ray source through analysis of the Doppler variations and ellipsoidal light variations of the faint K-star companion by McClintock and Remillard. The archive research, carried out under the supervision of the principal investigator, was the topic of the thesis submitted to the MIT Department of Physics by Kenneth Plaks in partial fulfillment of the requirements for the degree of Master of Science. Plaks' effort was focused on the elimination of fluctuations in the data due to errors in attitude solutions and other extraneous causes. The first products of his work were long-term light curves of the X-ray intensities in the various energy channels as functions of time during the time from outbursts in August 1975 to quiescence approximately 6 months later. These curves, are refined versions of the preliminary results published in 1976 (Matilsky et al. 1976). Smooth exponentials were fitted to these long term light curves to provide the basis for detrending the data, thereby permitting a calculation of residuals derived by subtracting the fitted curve from the data. The residuals were then analyzed by Fourier analysis to search for variations with the period of the binary orbit, namely 7.75 hours. No evidence of an orbital periodicity was found. However, the refined light curve provides a much clearer picture of the outburst and subsequent decay of the X-ray luminosity. In fact, there were two outbursts, each followed by an exponential decay with similar time constants of about 25 days. Previous evidence of a three-oscillation variation with a 7.8 day period were confirmed. Substantial theoretical effort has been devoted to attempts to account for the decay characteristics as the result of the gradual eating up of an accretion disk by a stellar-mass blackhole (e.g., Huang and Wheeler 1989). The improved decay curves will provide significant new constraints on the theoretical analyses

Some transport properties of sodium chloride

Imperial Users onl