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Articles 4951 - 4978 of 4978

Full-Text Articles in Physical Sciences and Mathematics

The Glaciation Level And Lowest Equilibrium Line Altitude In The High Canadian Arctic: Maps And Climatic Interpretation, G. H. Miller, Raymond S. Bradley, J. T. Andrews Jan 1975

The Glaciation Level And Lowest Equilibrium Line Altitude In The High Canadian Arctic: Maps And Climatic Interpretation, G. H. Miller, Raymond S. Bradley, J. T. Andrews

Raymond S Bradley

The glaciation level (GL) over the Queen Elizabeth Islands is highest over the main mountain areas. There are extremely steep gradients approaching 15 m km-t along the northwestern margin of the archipelago where the glaciation level is very low (300 m a.s.l.). Although the glaciation level mirrors topography on a gross scale, at the finer level the relationship breaks down, probably because of the effect of the mountains on precipitation patterns. There appears to be a sharp decline in the elevation of the glaciation level between the Canadian islands and northwest Greenland. The elevation of the lowest equilibrium line altitudes …

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Equilibrium-Line Altitudes, Mass Balance, And July Freezing-Level Heights In The Canadian High Arctic, Raymond S. Bradley Jan 1975

Equilibrium-Line Altitudes, Mass Balance, And July Freezing-Level Heights In The Canadian High Arctic, Raymond S. Bradley

Raymond S Bradley

Equilibrium-line altitudes on the White Glacier, Axel Heiberg Island, and the north-west sector of the Devon Ice Cap are shown to be closely related to mean July freezing-level heights at nearby upper-air weather stations. An inverse relationship between July freezing-level heights and mass balance on the Devon Ice Cap is also shown. Reasons for such correlations are suggested and some limitations of the relationship are outlined. Recent lowering of the freezing level in July is discussed in relation to the theoretical "steady-state" equilibrium-line altitudes in the Canadian high Arctic. It is suggested that positive mass-balance years have predominated over a …

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Optical Absorption Phenomena At Electrode Surfaces, Julian Tyson, T. S. West Jan 1974

Optical Absorption Phenomena At Electrode Surfaces, Julian Tyson, T. S. West

Chemistry Department Faculty Publication Series

No abstract provided.

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Observation Of Persistent Currents In A Saturated Superfluid Film, Robert Hallock, R. K. Galkiewicz Jan 1974

Observation Of Persistent Currents In A Saturated Superfluid Film, Robert Hallock, R. K. Galkiewicz

Robert Hallock

We report the first observation of a persistent flow around a closed path consisting entirely of saturated superfluid helium film in a macroscopic geometry in which the saturated vapor was in unconstrained proximity to the film

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Quasi-Isothermal Superfluid Film Oscillations, Robert Hallock Jan 1974

Quasi-Isothermal Superfluid Film Oscillations, Robert Hallock

Robert Hallock

We have carried out a detailed study of the frequency and damping of the oscillations in levels of two reservoirs of HeII which are coupled only via the mobile superfluid film. Our experiments cover the temperature range 1.2

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Quasi-Isothermal Superfluid Film Flow: Oscillations Between Two Reservoirs, Robert Hallock Jan 1974

Quasi-Isothermal Superfluid Film Flow: Oscillations Between Two Reservoirs, Robert Hallock

Robert Hallock

We have carried out a detailed study of the frequency and damping of the oscillations in levels of two reservoirs of HeII which are coupled only via the mobile superfluid film. Our experiments cover the temperature range 1.2

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X-Ray Scattering From Gaseous 3he And 4he At Small Momentum Transfer, Robert Hallock Oct 1973

X-Ray Scattering From Gaseous 3he And 4he At Small Momentum Transfer, Robert Hallock

Robert Hallock

Several experiments are described in which the structure factor S(k) was determined for gaseous 3He and 4He at temperatures near 5 K. In the momentum-transfer range 0.15

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Seasonal Climatic Fluctuations On Baffin Island During The Period Of Instrumental Records, Raymond S. Bradley Sep 1973

Seasonal Climatic Fluctuations On Baffin Island During The Period Of Instrumental Records, Raymond S. Bradley

Raymond S Bradley

Temperature and precipitation records for Baffin Island are examined on a seasonal basis for the last 40 to 50 years. Accumulation season temperatures (September to May) during the late 1960s were similar to those which prevailed 30 to 40 years ago. Ablation season temperatures (June, July, August) during the same period were cooler than for at least 30 years. Precipitation variations showed much less spatial coherence, but during the last 10 to 15 years there have been marked increases, mostly during winter months. These increases, accompanied by cooler summers and warmer winters, have led to increased glacierization of the area. …

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Secular Climatic Fluctuations In Southwestern Colorado, Raymond S. Bradley, Roger G. Barry Jan 1973

Secular Climatic Fluctuations In Southwestern Colorado, Raymond S. Bradley, Roger G. Barry

Raymond S Bradley

Precipitation and temperature data since records began in southwestern Colorado arc analyzed on a seasonal basis. Interstation correlations for recent years indicate that the region responds fairly uniformly to seasonal variations in precipitation, but this was not true earlier this century when precipitation variability was higher. Changes in the dependence of precipitation on elevation are also shown. Annual precipitation totals were low about 1860, 1900, 1930-35 and 1950-55. Mean annual temperatures appear to have fallen from about 1867 to about 1930 when the trend reversed. Overall, the climate of southwestern Colorado in the 1860s appears to have been warmer and …

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Neutron Scattering And The Dispersion Relation In He Ii At Small Momentum Transfer, Robert Hallock Jan 1973

Neutron Scattering And The Dispersion Relation In He Ii At Small Momentum Transfer, Robert Hallock

Robert Hallock

Weighted-least-squares fits to the small momentum transfer (k≤1 Å-1) results of Woods and Cowley have been carried out. We find that the neutron data presently available (i) are not of sufficient accuracy to determine whether or not quadratic terms are present in the dispersion relation and (ii) weakly favor positive dispersion in the absence of the quadratic term.

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Evidence That The Synchronized Production Of New Basal Bodies Is Not Associated With Dna Synthesis In Stentor Coeruleus, K. B. Younger, S. Banerjee, J. K. Kelleher, M. Winston, Lynn Margulis Sep 1972

Evidence That The Synchronized Production Of New Basal Bodies Is Not Associated With Dna Synthesis In Stentor Coeruleus, K. B. Younger, S. Banerjee, J. K. Kelleher, M. Winston, Lynn Margulis

Lynn Margulis (1938 - 2011)

Stentors were induced to produce synchronously thousands of new ciliated oral membranellar band basal bodies in less than 3 h. DNA synthesis does not accompany this process, as determined by [3H]thymidine incorporation into isolated bands and by sensitivity to DNA synthesis inhibitors (mitomycin C, ethidium bromide, cytosine arabinoside and hydroxyurea). Yet DNA could be detected in the cortex and the band at basal body sites by autoradiography. Since [3H]thymidine incorporation into membranellar band was eliminated in concentrations of ethidium bromide that had no effect on basal body formation, the previous reports of ciliate kinetosomal (basal body) DNA are interpreted as …

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Small Momentum Transfer Structure Factor Of Quantum Liquids, Robert Hallock Jan 1971

Small Momentum Transfer Structure Factor Of Quantum Liquids, Robert Hallock

Robert Hallock

The liquid structure factor of 3He has been determined in the momentum-transfer range 0.2 to 1.0 Å-1. At temperatures near 0.4 K there is evidence for a gentle change of slope of the structure factor in the region near 0.35 Å-1 Comparison with the work on helium-4 suggests that the observed behavior is a general feature of the two fluids.

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An Inexpensive Target Cell For The Study Of Liquids And Gases By X-Ray Scattering, Robert Hallock Jan 1971

An Inexpensive Target Cell For The Study Of Liquids And Gases By X-Ray Scattering, Robert Hallock

Robert Hallock

No abstract provided.

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New Phylogenies Of The Lower Organisms: Possible Relation To Organic Deposits In Precambrian Sediment, Lynn Margulis Jul 1969

New Phylogenies Of The Lower Organisms: Possible Relation To Organic Deposits In Precambrian Sediment, Lynn Margulis

Lynn Margulis (1938 - 2011)

Classical phylogenies of the lower organisms are based on assumptions recently claimed to be erroneous. Alternative assumptions, more consistent with modern genetic and biochemical data, lead to the construction of new phylogenies. The new phylogenies (one for prokaryote organisms and one for eukaryotes) based on the symbiotic theory of the origin of eukaryotic organelles predict the nature and sequence of organic deposits on the Precambrian earth. Even if incorrect, these phylogenies present a modern framework upon which to compare the many recent reports of organic remains in sediment.

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Deuteron Magnetic Dipole Disintegration By 180° Electron Scattering, Gerald Alvin Peterson, W C. Barber Oct 1962

Deuteron Magnetic Dipole Disintegration By 180° Electron Scattering, Gerald Alvin Peterson, W C. Barber

Gerald Alvin Peterson

The magnetic dipole disintegration of the deuteron has been measured for excitation energies up to 16 MeV in the presence of relatively small electric multipole contributions by using a method of inelastic electron scattering at 180°. Electrons of initial energy 41.5 MeV were magnetically deflected before and after scattering so that those scattered at 180° entered a magnetic spectrometer set at 160° with respect to the incident beam. The experimental cross sections measured relative to elastic scattering from the proton are higher than predicted by the electrodisintegration theory of Jankus. The discrepancy may be an indication of mesonic exchange currents …

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Laotian Agricultural Statistics, Joel Halpern Apr 1961

Laotian Agricultural Statistics, Joel Halpern

Anthropology Department Faculty Publication Series

No abstract provided.

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Laotian Agricultural Statistics, Joel Halpern Apr 1961

Laotian Agricultural Statistics, Joel Halpern

Joel M. Halpern

No abstract provided.

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Government Statistics, Joel Halpern Jan 1961

Government Statistics, Joel Halpern

Anthropology Department Faculty Publication Series

No abstract provided.

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Government Statistics In Laos, Joel Halpern Jan 1961

Government Statistics In Laos, Joel Halpern

Emeritus Faculty Author Gallery

No abstract provided.

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Economic And Related Statistics Dealing With Laos, Joel Halpern Jan 1961

Economic And Related Statistics Dealing With Laos, Joel Halpern

Anthropology Department Faculty Publication Series

No abstract provided.

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Laotian Health Statistics, Joel Halpern Jan 1961

Laotian Health Statistics, Joel Halpern

Anthropology Department Faculty Publication Series

No abstract provided.

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Government Statistics In Laos, Joel Halpern Jan 1961

Government Statistics In Laos, Joel Halpern

Joel M. Halpern

No abstract provided.

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Laotian Health Statistics, Joel Halpern Jan 1961

Laotian Health Statistics, Joel Halpern

Joel M. Halpern

No abstract provided.

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Arctic Gold, Alaska, Joel Halpern Mar 1951

Arctic Gold, Alaska, Joel Halpern

Emeritus Faculty Author Gallery

To armchair travelers, especially in the United States, few places have a stronger allure than far-off Alaska. Now that the "wild and woolly" west is really alive only so far as it serves to accentuate our historical heritage, this land of the far north has become our last frontier. To the geologist, mineralogist, and, I might add, even to the layman, one of the most interesting features of the territory is its large placer gold deposits. Every American boy has heard of the Nome gold rush, and the more literarily adventurous have undoubtedly delved into the sagas of Jack London. …

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Arctic Gold, Joel Halpern Mar 1951

Arctic Gold, Joel Halpern

Anthropology Department Faculty Publication Series

To armchair travelers, especially in the United States, few places have a stronger allure than far-off Alaska. Now that the "wild and woolly" west is really alive only so far as it serves to accentuate our historical heritage, this land of the far north has become our last frontier. To the geologist, mineralogist, and, I might add, even to the layman, one of the most interesting features of the territory is its large placer gold deposits. Every American boy has heard of the Nome gold rush, and the more literarily adventurous have undoubtedly delved into the sagas of Jack London. …

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Arctic Gold, Alaska, Joel Halpern Mar 1951

Arctic Gold, Alaska, Joel Halpern

Joel M. Halpern

To armchair travelers, especially in the United States, few places have a stronger allure than far-off Alaska. Now that the "wild and woolly" west is really alive only so far as it serves to accentuate our historical heritage, this land of the far north has become our last frontier. To the geologist, mineralogist, and, I might add, even to the layman, one of the most interesting features of the territory is its large placer gold deposits. Every American boy has heard of the Nome gold rush, and the more literarily adventurous have undoubtedly delved into the sagas of Jack London. …

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Contribution To The Chemistry Of Oils And Fats With Particular Reference To Butter Fat, Edward Bertram Holland Jan 1915

Contribution To The Chemistry Of Oils And Fats With Particular Reference To Butter Fat, Edward Bertram Holland

Doctoral Dissertations 1896 - February 2014

Experiments in animal nutrition have constituted a prominent line of investigation at the Massachusetts Experiment Station ever since its organisation, but not until 1890 was any attempt made by this station to ascertain the effect of feed on the composition of butter fat.

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An Application Of The Conductivity And Freezing Point Methods For The Determination Of The Molecular Weights Of Electrolytes, S. Francis Howard Jan 1901

An Application Of The Conductivity And Freezing Point Methods For The Determination Of The Molecular Weights Of Electrolytes, S. Francis Howard

Doctoral Dissertations 1896 - February 2014

Object: To determine whether in such compounds as potassium permanganate, ferric chloride, etc., the formula should be written in its simplest form or should be doubled.

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