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

183944 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 4653, results 116301 - 116325

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
On-line estimation of nonlinear physical systems
G. Christakos
1988, Mathematical Geology (20) 111-133
Recursive algorithms for estimating states of nonlinear physical systems are presented. Orthogonality properties are rediscovered and the associated polynomials are used to linearize state and observation models of the underlying random processes. This requires some key hypotheses regarding the structure of these processes, which may then take account of a...
Oxygen isotope variations in granulite-grade iron formations: constraints on oxygen diffusion and retrograde isotopic exchange
Z.D. Sharp, J. R. O’Neil, E.J. Essene
1988, Contributions to Mineralogy and Petrology (98) 490-501
The oxygen isotope ratios of various minerals were measured in a granulite-grade iron formation in the Wind River Range, Wyoming. Estimates of temperature and pressure for the terrane using well calibrated geothermometers and geobarometers are 730??50?? C and 5.5??0.5 kbar. The mineral constraints on fluid compositions in the iron formation...
Bacterial ethane formation from reduced, ethylated sulfur compounds in anoxic sediments
R.S. Oremland, Michael J. Whiticar, F.E. Strohmaier, R.P. Kiene
1988, Geochimica et Cosmochimica Acta (52) 1895-1904
Trace levels of ethane were produced biologically in anoxic sediment slurries from five chemically different aquatic environments. Gases from these locations displayed biogenic characteristics, having 12C-enriched values of δ13CH4 (−62 to −86%.), δ13C2H6 (−35 to −55%.) and high ratios (720 to 140,000) of CH4[C2H6+ C3H8]">CH4[C2H6+ C3H8]. Endogenous...
Further comments on sensitivities, parameter estimation, and sampling design in one-dimensional analysis of solute transport in porous media
Debra S. Knopman, Clifford I. Voss
1988, Water Resources Research (24) 225-238
Sensitivities of solute concentration to parameters associated with first-order chemical decay, boundary conditions, initial conditions, and multilayer transport are examined in one-dimensional analytical models of transient solute transport in porous media. A sensitivity is a change in solute concentration resulting from a change in a model parameter. Sensitivity analysis is...
Comparison of hatchery-reared lake trout stocked as fall fingerlings and as spring yearlings in Lake Ontario
Joseph H. Elrod, David E. Ostergaard, Clifford P. Schneider
1988, North American Journal of Fisheries Management (8) 455-462
We made 16 paired releases of lake trout Salvelinus namaycush of four year classes (1979–1982) at five locations to compare survival and growth of hatchery-reared fish stocked as fall fingerlings (FF) and as spring yearlings (SY). Comparisons were based on fish at ages 2–8 recovered with bottom trawls, with gill nets, and...
Preface
E. Kurkstak, Y. Kuroda, K. Maramorosch, D. P. Anderson
Y. Kuroda, E. Kurstak, K. Maramorosch, editor(s)
1988, Book chapter, Invertebrate and Fish Tissue Culture
No abstract available at this time...
Graptemys barbouri
R.A. Sanderson, J.E. Lovich
1988, Book chapter, Catalogue of American Amphibians and Reptiles
No abstract available at this time...
Chaparral
Jon E. Keeley, S.C. Keeley
M.G. Barbour, W.D. Billings, editor(s)
1988, North American terrestrial vegetation. 165-207
No abstract available at this time...
Caterpillars
J. A. Howell
1988, Book chapter, Children's Encyclopedia.
No abstract available at this time...
Polar Bear
S.D. Amstrup, DeMaster
J.W. Lentfer, editor(s)
1988, Report, Selected marine mammals of Alaska: Species accounts with research and management recommendations, U. S. Marine Mammal Commission, Washington, D. C
Polar bears are long-lived, late-maturing carnivores that have relatively low rates of reproduction and natural mortality. Their populations are susceptible to disturbance from human activities, such as the exploration and development of mineral resources or hunting. Polar bear populations have been an important renewable resource available to coastal communities throughout...
Fixed-wing airplane versus helicopter surveys of manatees (Trichechus manatus)
Galen B. Rathbun
1988, Marine Mammal Science (4) 71-75
The abundance of manatees, as with most marine mammals, is difficult to determine because they are visible for only short periods of time while at the surface of the water (Eberhardt et al. 1979, Powell et al. 1981). Aerial surveys are generally considered to be the most accurate method of...