Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

165969 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 5877, results 146901 - 146925

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Structural charge site influence on the interlayer hydration of expandable three-sheet clay minerals
Raymond L. Kerns Jr., Charles J. Mankin
1968, Clays and Clay Minerals (16) 73-81
Previous investigations have demonstrated the influences of interlayer cation composition, relative humidity, temperature, and magnitude of interlayer surface charge on the interlayer hydration of montmorillonites and vermiculites. It has been suggested that the sites of layer charge deficiencies may also have an influence upon the amount of hydration that can...
Studies in the system MgO-SiO2-CO2-H2O(I): The activity-product constant of chrysotile
P. B. Hostetler, C. L. Christ
1968, Geochimica et Cosmochimica Acta (32) 485-497
Chrysotile dissolves congruently in water according to the reaction: Mg3Si2O6(OH)4c + 5H2Ol = 3Mgaq2+ + 6OHaq− + 2H4SiO4aq. Experimental determination of the activity-product constant of chrysotile, Kchr = [Mg2+]3[OH−]6[H4SiO4aq]2, at 90°C, yields the value of Kchr = 10−49.2 ± 100.5. A synthetic sample and a natural sample from New Idria, California, were used in the determination.Values of Kchr were calculated for temperatures...
The alewife
Stanford H. Smith
1968, Limnos (1) 12-20
When the first alewife, Alosa pseudoharengus, was discovered in Lake Michigan near South Manitou Island on May 5, 1949, few people would have guessed that it would become the best known fish of the lake in less than two decades. Now it competes only with the coho salmon in...
Annulus formation on scales of four species of coregonids reared under artificial conditions
Walter J. Hogman
1968, Journal of the Fisheries Research Board of Canada (25) 2111-2122
Scales from known-age coregonids reared in the laboratory were examined to determine when annuli formed and to learn possible factors of their formation. Scales were taken monthly from marked fish for periods up to 21 months. Scales were also examined from fish that died and from preserved specimens of young-of-the-year...
Two hermaphroditic alewives from Lake Michigan
Thomas A. Edsall, Margaret I. Saxon
1968, Copeia (1968) 406-407
Hermaphroditism has been reported frequently among many of the Clupeidae, but only one account of hermaphroditism has been published for the alewife, Alosa pseudoharengus. Rothschild discovered four hermaphroditic alewives among 444 fish he examined from Cayuga Lake, New York. We recently collected two hermaphroditic alewives from Lake Michigan....
Comparative embryology of five species of lampreys of the upper Great Lakes
Allen J. Smith, John H. Howell, George W. Piavis
1968, Copeia (1968) 461-469
The four species of lampreys native to the upper Great Lakes (American brook lamprey, Lampetra lamotteni; chestnut lamprey, Ichthyomyzon castaneus; northern brook lamprey, I. fossor; and silver lamprey, I. unicuspis) were collected in various stages of their life cycle and maintained in the laboratory until sexually mature. Secondary sex characters...
Species succession and fishery exploitation in the Great Lakes
Stanford H. Smith
1968, Journal of the Fisheries Research Board of Canada (25) 667-693
The species composition of fish in the Great Lakes has undergone continual change since the earliest records. Some changes were caused by enrichment of the environment, but others primarily by an intensive and selective fishery for certain species. Major changes related to the fishery were less frequent before the late...
Daytime distribution of Pontoporeia affinis off bottom in Lake Michigan
LaRue Wells
1968, Limnology and Oceanography (13) 703-705
The vertical migration of the amphipod Pontoporeia affinis in Lake Michigan has been well documented by Wells, Marzolf, and McNaught and Hasler. Wells and Marzolf observed Pontoporeia off bottom only at night. McNaught and Hasler, however, found Pontoporeia above the bottom shortly after noon in a 24-hr study on 12...
Seasonal depth distribution of fish in southeastern Lake Michigan
LaRue Wells
1968, Fishery Bulletin (67) 1-15
This study is based on systematic seasonal bottom trawling between 3 and 50 fathoms (5.5 and 91.5 m.) from February to November 1964 and supplementary information from other experimental fishing at additional depths and with other gear. The seasonal depth distribution of eight common species is described, and temperature relations...
Distribution and abundance of the Japanese snail, Viviparus japonicus, and associated macrobenthos in Sandusky Bay, Ohio
David R. Wolfert, Jarl K. Hiltunen
1968, Ohio Journal of Science (68) 32-40
A survey of the macrobenthos of Sandusky Bay, Lake Erie, in June, 1963, provided information on the abundance and distribution of the introduced Japanese snail, Viviparus japonicus, which has become a nuisance to commercial seine fishermen. The abundance and distribution varied considerably within the bay; at the time of the...
Production of sea lamprey larvae from nests in two Lake Superior streams
Patrick J. Manion
1968, Transactions of the American Fisheries Society (97) 484-486
The life history of the landlocked sea lamprey, Petromyzon marinus, has been described by several authors, the two most recent of which are Applegate and Wigley. The only information on the production of larvae from nests of the sea lamprey was reported by Applegate, who counted the larvae from three...
An improved girthometer for studies of gill net selectivity
Richard S. Wydoski, David R. Wolfert
1968, Progressive Fish-Culturist (30) 62-64
Gill nets are effective for collecting samples of many fish species. These nets may be highly selective in their catch, depending on the mesh size or sizes used and on the size distribution and body shape of the fish in the population. Early studies related mesh selectivity to...
Gas chromatographic separation and quantitative estimation of barbiturate mixtures in solid dosage forms
J. L. Allen
1968, Journal of the Association of Official Analytical Chemists (51) 619-621
A gas chromatographic method has been described for the analysis of mixed barbiturates in solid dosage forms. Analysis on a 10% SE-30 column gave good separations for butabarbital, amobarbital, secobarbital, pentobarbital, and/or phenobarbital; amobarbital is not separated adequately from pentobarbital. An internal standard, mephobarbital, is used to minimize injection errors....
A surface tow net for collection of parasitic-phase sea lampreys
Frederick H. Dahl
1968, Progressive Fish-Culturist (30) 183-184
A STUDY OF MIGRATORY BEHAVIOR of parasitic sea lampreys (Petromyzon marinus) in the Great Lakes required a means of capturing lampreys for tagging and releasing in St. Marys River, Lake Huron. Smith and Elliott (1953) fished specially made gill and trap nets for sea lampreys, but stationary nets could not...
An electric beam trawl for the capture of larval lampreys
Alberton McLain, Frederick H. Dahl
1968, Transactions of the American Fisheries Society (97) 289-293
The chemicals used to control the sea lamprey, Petromyzon marinus, in the Great Lakes have drastically reduced populations of larval lampreys in tributary streams. These larvicides are too costly and difficult to apply, however, in inland lakes, estuaries, and bays. Populations of sea lampreys in these areas constitute...
Movements of adult lake trout in Lake Superior
Jerold F. Rahrer
1968, Transactions of the American Fisheries Society (97) 481-484
Returns from mature lake trout (Salvelinus namaycush) tagged in western Lake Superior in 1959 and 1962-65 described here suggest that trout disperse widely from the spawning grounds after spawning and return in subsequent years. Although the data were not extensive, returns from lake trout tagged near Keweenaw Point in 1950...
Geology and ground-water resources of Fillmore County, Nebraska, with a section on chemical quality of the water
Charles Franklin Keech, V. H. Dreeszen, L. R. Petri
1968, Water Supply Paper 1839-L
Fillmore County, an area 24 miles square, lies in the eastern part of the Nebraska loess plain. Although tributaries of the Big Blue River have eroded valleys into this plain, much of the original surface is intact. Broad flats and numerous shallow undrained depressions characterize the plain. The county is...
Electrophoretic separation of fish brain esterases
Charles O. Knowles, Suresh K. Arurkar, James W. Hogan
1968, Journal of the Fisheries Research Board of Canada (25) 1517-1519
Fish brains were homogenized in an all-glass Potter-Elvehjem-type tissue grinder in 40% sucrose solution. The homogenate concentration was 10 brains/ml for both the bluegill and channel catfish. The brei was centrifuged at 34,700 g for 30 min at 5 C, and 30 J.lliters of the supernatant were used per column...
Some effects of mirex on two warm-water fishes
Charles C. Van Valin, Austin K. Andrews, Lafayette L. Eller
1968, Transactions of the American Fisheries Society (97) 185-196
The effects of mirex on two species of warm-water fishes were studied in three experiments in which the fish were exposed either by feeding a mirex-treated diet, or by treating the holding ponds with a mirex formulation. Bluegills were used in the feeding experiment, where three different levels of mirex...