Land use Effects on Ground Water Quality in Carbonate Rock Terrain

A control site with a natural setting and an experimental site with significant agriculture land use were studied in the Ozark Region of Arkansas in order to determine the effect of land use on water quality in a carbonate rock terrain. The vast majority of the two sites have the Boone Limestone exposed which combined with the underlying St. Joe is the major aquifer for drinking water in the area. The sites also are similar in terms of lineament patterns (number, length and orientation), soil, slope and vegetation. Ground water samples were collected primarily from springs during three seasons (late summer-early fall, winter and spring). All three seasonal collections exhibited statistically higher NO3 (2.31 versus 0.81 mg/L) and Cl (9.9 versus 2.7 mg/L) concentrations in the experimental site. During the winter and spring collections, the experimental site also exhibited statistically higher concentrations (0.5 to 3x) of PO4, SO4, Na, K and Ca. Heavy metals were analyzed in the winter samples; however, the differences between the two sites were small because the absolute values for the two sites were low. For example, the largest difference for a heavy metal was 19 μg/L for Mn (12 versus 31 μg/L). Bacteria determined from the spring season samples showed that the experimental site had significantly higher counts of fecal coliform (86 versus 0.4 col - onies/100 mL) and fecal Streptococcus (39 versus 3 colonies/100 mL) types than the control site. Three springs were also sampled periodically following a rain event of 10 cm. Whereas, levels of specific conductance, NO3, Ca and Na decreased in all three springs, PO4, K, SO4 and fecal coliform increased significantly, primarily in the two experimental springs. The increase of these parameters indicates that they are more available in the experimental area. Based on these results and elemental correlations, it appears that cattle manure, the spreading of chicken manure and commercial fertilizers, and septic tank effluent, individually or in combination, are affecting the water quality of the experimental site. However, most of the ground water samples meet EPA drinking water standards with the possible exception of bacteria

Gamma Ray Bursts in the Era of Rapid Followup

We present a status report on the study of gamma-ray bursts (GRB) in the era of rapid follow-up using the world's largest robotic optical telescopes - the 2-m Liverpool and Faulkes telescopes. Within the context of key unsolved issues in GRB physics, we describe (1) our innovative software that allows real-time automatic analysis and interpretation of GRB light curves, (2) the novel instrumentation that allows unique types of observations (in particular, early time polarisation measurements) and (3) the key science questions and discoveries to which robotic observations are ideally suited, concluding with a summary of current understanding of GRB physics provided by combining rapid optical observations with simultaneous observations at other wavelengths.Comment: 20 pages, 12 figures; Review article accepted for publication in Advances in Astronomy, special issue 'Robotic Astronomy (Hindawi Publishing Corporation)

Addendum no. 1 to final development report

Pseudo-linearity concept impact on linear filters designed to ease pulse crowding effects at high bit densitie

A computer simulation of digital recording Final development progress report, 29 Dec. 1966 - 29 Dec. 1967

Fourier series digital computer simulation of tape recording process - signal detection in prescence of white Gaussian nois

Land use change detection with LANDSAT-2 data for monitoring and predicting regional water quality degradation

There are no author-identified significant results in this report

Close-packed structures and phase diagram of soft spheres in cylindrical pores

It is shown for a model system consisting of spherical particles confined in cylindrical pores that the first ten close-packed phases are in one-to-one correspondence with the first ten ways of folding a triangular lattice, each being characterized by a roll-up vector like the single-walled carbon nanotube. Phase diagrams in pressure-diameter and temperature-diameter planes are obtained by inherent-structure calculation and molecular dynamics simulation. The phase boundaries dividing two adjacent phases are infinitely sharp in the low-temperature limit but are blurred as temperature is increased. Existence of such phase boundaries explains rich, diameter-sensitive phase behavior unique for cylindrically confined systems

Trace Element Composition of Stream Sediments an Integrating Factor for Water Quality

Bottom sediments, suspended sediments, and water were sampled along 130 miles of the Buffalo River in northern Arkansas. The water and acid extracts of the suspended sediments and the minus 95 mesh fraction of the bottom sediments were analyzed by atomic absorption spectrometry. All samples were analyzed for Na, K, Mg, Ca, Zn, Cd, Cu, Pb, Fe, Co, Cr, Ni, and Mn. Selected bottom samples also were analyzed by As, Hg, and Zr. Zr was determined by x-ray fluorescence. Li and Sr were determined for selected water and suspended sediment samples. There is a general decrease downstream in Fe, Cu, Cr, Ni, Mn, Pb, K, and Na in the bottom sediments as the drainage area increases in carbonate rock and decreases in shale. The elements Mg, Ca, Zn, and Cd increase in bottom sediments downstream. The values for these elements in the water, especially the major elements, also correspond closely with the geology of the region. Tributaries are sites of abrupt rise and fall of metal values, within a few miles, from background to anomalously high values to background, especially tributaries draining Zn and Pb mineralized areas. The bottom sediments are mainly quartz and chert grains. These grains apparently are coated with hydrous iron oxide which acts as a sorbent for many of the elements and is a dominant transport mechanism for acid extractable Co, Cr, Ni, Cu, Mn, and K. Other acid extractable metals, particularly Mg, Ca, Zn, Cd, and Pb, are mostly in clastic grains. Graphic representation of the Langmuir equation for Mn is consistent with adsorption of Mn by iron in both bottom sediments and suspended sediments. On the basis of the volume of water collected, all the elements except Fe are more concentrated in the water than in the suspended sediments. Fe concentration of the suspended sediments increases with increasing flow because the suspended load is increased. The Mn/Fe ratio of the suspended sediments is approximately equal to or greater than that of the bottom sediments. The Mn/Fe ratio of suspended sediments relative to that of the bottom sediments increases downstream, possibly because of an autocatalytic effect of Mn precipitation. The relationship between sediment and water concentrations is not clear from the data because of the restricted concentration ranges for some elements in the suspended sediment and water. The sediment from the Buffalo River can be used to estimate grossly the concentration of elements in the water