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Page 6497, results 162401 - 162425

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Lake Ontario phytoplankton, September 1964
Roann E. Ogawa
1969, Technical Report 14
Phytoplankton counts on samples collected in Lake Ontario on September 8-18, 1964, showed that green algae were the dominant plankters and diatoms were of secondary importance. The greatest abundance of phytoplankton was close to shore from Toronto, along the southern shore of the lake, and up the eastern shore to...
Planktonic diatoms of Lake Ontario
Jerry F. Reinwand
1969, Technical Report 14
The major species of diatoms in surface collections from Lake Ontario in September 1964 were Asterionella formosa, Fragilaria crotonensis, and Tabellaris fenestrata. Dominant species in the deep-water samples were Stephanodiscus astraea, S. astraea var. mintula, and F. crotonensis. The diatom flora in surface collections varied among several stations in the...
A paleomagnetic study of secular variation in New Zealand
A. Cox
1969, Earth and Planetary Science Letters (6) 257-267
Ancient secular variation in New Zealand was determined from paleomagnetic measurements on 22 volcanic formations with ages of less than 0.68 m.y. The angular standard deviation from the field of an axial dipole is 13.2° with 95% confidence limits between 10.9° and 16.7°....
Lithium and potassium absorption, dehydroxylation temperature, and structural water content of aluminous smectites
Leonard Gene Schultz
1969, Clays and Clay Minerals (17) 115-149
X-ray analysis of Li+- and K+-saturated samples, differential thermal analysis (DTA), thermal gravimetric analysis (TGA), and chemical analysis of 83 samples enable a distinction to be made between Wyoming, Tatatilla, Otay, Chambers, and non-ideal types of montmorillonite, and between ideal and non-ideal types of beidellite. The Greene-Kelly Li+-test differentiates between...
Alpine-type sensu strictu(ophiolitic) peridotites: Refractory residues from partial melting or igneous sediments? A contribution to the discussion of the paper: "The origin of ultramafic and ultrabasic rocks" by P.J. Wyllie
T. P. Thayer
1969, Tectonophysics (7) 511-516
Although Alpine peridotites and basaltic lavas are widely associated in eugeosynclines and oceanic areas, their genetic ties are obscure. Three major characteristics of olivine-rich Alpine peridotite and dunite—relict cumulus textures, aggregated masses of chromitite, and intimate association with magnesium-rich gabbro — cannot be...
Pecoraite, Ni6Si4O10(OH)8, nickel analog of clinochrysotile, formed in the wolf creek meteorite
G. T. Faust, J. J. Fahey, B. Mason, E.J. Dwornik
1969, Science (165) 59-60
Pecoraite is a new phase in the natural system H2O-NiO-MgO- SiO2, the nickel analog of clinochrysotile. It occurs in cracks in the Wolf Creek meteorite in Australia where it was formed under hydrothermal conditions. Particles of pecoraite are very small curved plates which have begun to coil; some have achieved...
Oxygen isotope fractionation in divalent metal carbonates
J. R. O’Neil, R.N. Clayton, T.K. Mayeda
1969, Journal of Chemical Physics (51) 5547-5558
Equilibrium fractionation factors for the distribution of 18O between alkaline‐earth carbonates and water have been measured over the temperature range 0–500°C. The fractionation factors α">αα can be represented by the equations<span id="MathJax-Element-2-Frame"...
Invertebrate macrobenthos of western Lake Superior
Jarl K. Hiltunen
1969, Michigan Academician (1) 123-133
The present report contributes to knowledge of the relative abundance of major groups of benthic invertebrates in western Lake Superior, primarily in the Apostle Islands region. Observations are made on the depth habitation of certain species, and some of the fauna are compared to that in some of the...
Hydrology of the San Luis Valley, south-central Colorado
P. A. Emery, A. J. Boettcher, R.J. Snipes, H.J. Mcintyre Jr.
1969, Report
An investigation of the water resources of the Colorado part of the San Luis Valley was begun in 1966 by the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board. (See index map, fig. 1). The purpose of the investigation is to provide information for planning and implementing...
Selective feeding by juvenile diving ducks in summer
James C. Bartonek, J.J. Hickey
1969, The Auk (86) 443-457
Waterfowl often fail to use foods that seem plentiful to the investigator. The extent to which selective feeding or rejection of foods is a function of behavioral and morphological adaptations of the species, conditioned behavior of the individual, or individual preference for certain foods has not been appraised. The objectives...
Rearing of sea lamprey, Petromyzon marinus, embryos in distilled water
George W. Piavis, John H. Howell
1969, Copeia (1969) 204-205
Most embryological studies of lampreys in the Great Lakes have been conducted with filtered water from Lake Huron. Although this water was entirely satisfactory for the earlier work, the present need for knowledge of the effects of various compounds on embryological development requires that the initial medium be sterile....
Determination of traces of silver in waters by anion exchange and atomic absorption spectrophotometry
T. T. Chao, M. J. Fishman, J.W. Ball
1969, Analytica Chimica Acta (47) 189-195
A method has been developed for the accurate determination of 0.1–1 μg of silver per liter of water. The method permits stabilization of silver in water without loss to container walls. Optimum conditions have been established for the complete recovery of silver from water with an anion-exchange column, for quantitative...
Extraction of vanadium into isobutyl methyl ketone
Hans J. Crump-Wiesner, W.C. Purdy
1969, Talanta (16) 124-129
Because of its advantages in atomic-absorption spectroscopy, isobutyl methyl ketone was chosen as organic solvent for an extraction study on vanadium. Of eight chelating agents which were evaluated for completeness of extraction, ease of use, working pH range, and freedom from interference, cupferron was judged best.<div...