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Page 5819, results 145451 - 145475

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Mallard hatching from an egg cracked by freezing
R. J. Greenwood
1969, The Auk (86) 752-754
The eggs of early-nesting waterfowl in North Dakota are frequently exposed to subfreezing temperatures. Mallards (Anas platyrhynchos) and Pintail (Anas acuta), normally the first ducks to arrive in the spring, begin limited early nesting in min-April. Nighttime temperatures during this period frequently drop below freezing, and late spring blizzards are...
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....
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...
Evaluation of lamprey larvicides in the Big Garlic River and Saux Head Lake
Patrick J. Manion
1969, Journal of the Fisheries Research Board of Canada (26) 3077-3082
Bayluscide (5,2′-dichloro-4′-nitrosalicylanilide) and TFM (3-trifluoromethyl-4-nitrophenol) were evaluated as selective larvicides for control of the sea lamprey, Petromyzon marinus, in the Big Garlic River and Saux Head Lake in Marquette County, Michigan. Population estimates and movement of ammocetes were determined from the recapture of marked ammocetes released before chemical treatment. In 1966...
Rapid determination of filterable residue in natural waters
Herbert E. Allen, Charles W. Bacon
1969, Journal - American Water Works Association (61) 355-356
The most widely used procedures for determining filterable residue (total dissolved solids) in water are macromethods given in Standard Methods. Although macromethods give good results, they require large amounts of water and long drying times. This report describes a microtechnique for determining filterable residue that requires only 0.05...
Seasonal fluctuations of Lake Michigan diatoms
Ruth E. Holland
1969, Limnology and Oceanography (14) 423-436
Diatoms were collected in four areas of Lake Michigan and in southern Green Bay from April to early November 1965. The flora of the lake was characterized by Fragilaria crotonensis, Tabellaria flocculosa, Melosira islandica, Cyclotella 'glomerata-stelligera,' Cyclotella michiganiana, Asterionella formosa, and Stephanodiscus tenuis. Stephanodiscus niagarae always dominated the diatom biomass...
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...
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...
A purple-colored 1M mica clay from Silverton, Colorado
Pei-Lin Tien
1969, Clays and Clay Minerals (17) 245-249
A purple-colored clay of 1M mica polymorph in association with lead-zinc ore was collected from an abandoned mine dump near Silverton, Colorado. Electron micrographs show that the crystallites of the clay are less than 2µ in size and have poorly developed hexagonal outlines. Differential thermal and i.r. absorption analyses indicate...
The morphology and chronology of a landslide near Dillon Dam, Dillon, Colorado
E.E. Wahlstrom, T. C. Nichols Jr.
1969, Engineering Geology (3) 149-174
Investigations were made of a landslide at the Dillon Dam site, Dillon, Colo., that included detailed laboratory and field analyses of the mineralogy, chemistry, and physical properties of landslide materials and the bedrock formations from which they were derived. These investigations provide an understanding of the relative importance of various...
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...
Interstitial brines in playa sediments
B.F. Jones, A. S. Van Denburgh, A.H. Truesdell, S.L. Rettig
1969, Chemical Geology (4) 253-262
Study of several closed drainages in the Great Basin has shown that the interstitial solutions of shallow, fine-grained playa deposits store a large quantity of dissolved solids and are often more concentrated than associated lakes and ponds, except in peripheral zones of stream or ground-water inflow. These interstitial fluids,...
Pyrolysis of humic and fulvic acids
R.L. Wershaw, G.E. Bohner Jr.
1969, Geochimica et Cosmochimica Acta (33) 757-762
Pyrolysis of humic and fulvic acids isolated from a North Carolina soil yields a variety of aromatic, heterocyclic and straight chain organ compounds. The pyrolysis products identified by gas chromatography and mass spectrometry indicate that humic and fulvic acids have aromatic and polysaccharide...
Sediment Transport in Streams in the Umpqua River Basin, Oregon
C. A. Onions
1969, Report
This report presents tables of suspended-sediment data collected from 1956 to 1967 at 10 sites in the Umpqua River basin. Computations based on these data indicate that average annual suspended-sediment yields at these sites range from 137 to 822 tons per square mile. Because available data for the Umpqua River...
Selected hydrologic data, southern Utah and Goshen Valleys, Utah
R.M. Cordova
1969, Utah Basic-Data Release 16
The purpose of this report is to present basic geologic, ground-water, surface-water, and quality of water data that are useful for the study and effective development of the water resources of southern Utah and Goshen Valleys. This report supplements an interpretive report which will be published later.Much of the basic...