Magnetic Reversal Phenomena in Pyrrhotite     

V. L. S. Bhimasankaram  M. Lewis 《Geophysical Journal International》1966,11(5):485-497

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SULFUR IN ACHONDRITIC METEORITES     

Everett K. Gibson  Carleton B. Moore  Thomas M. Primus  Charles F. Lewis 《Meteoritics & planetary science》1985,20(3):503-511

Total sulfur abundances have been measured for 48 achondrites. For twenty eucrites they ranged from 370 to 3700 μgS/g with a median sulfur content of 1180 μgS/g. Sulfur abundances for howardites ranged from 1490 to 3240 μgS/g and had a median sulfur concentration of 2340 μgS/g. Diogenites' sulfur abundances ranged from 130 to 3170 μgS/g, with a median value of 1280 μgS/g. Four shergottites had a median sulfur content of 1940 μgS/g and ranged from 740 to 2540 μgS/g. Enstatite achondrites contained the greatest sulfur abundances of any achondrite group. They ranged from 2450 to 8580 μgS/g and had a median sulfur content of 6020 μgS/g. A single Chassignite had a sulfur concentration of 360 μgS/g. The wide variations in sulfur concentrations for the achondrites reflect the small scale heterogeneous nature of these unique extraterrestrial materials due in large part to discrete sulfide mineral grains.  相似文献   

The Anglo-Australian Observatory 2dF facility   总被引：1，自引：0，他引：1  

I. J. Lewis  R. D. Cannon  K. Taylor  K. Glazebrook  J. A. Bailey  I. K. Baldry  J. R. Barton  T. J. Bridges  G. B. Dalton  T. J. Farrell  P. M. Gray  A. Lankshear  C. McCowage  I. R. Parry  R. M. Sharples  K. Shortridge  G. A. Smith  J. Stevenson  J. O. Straede  L. G. Waller  J. D. Whittard  J. K. Wilcox  K. C. Willis 《Monthly notices of the Royal Astronomical Society》2002,333(2):279-299

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The 2dF Galaxy Redshift Survey: spectra and redshifts     

Matthew Colless  Gavin Dalton  Steve Maddox  Will Sutherland  Peder Norberg  Shaun Cole  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Chris Collins  Warrick Couch  Nicholas Cross  Kathryn Deeley  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Carlos S. Frenk  Karl Glazebrook  Carole Jackson  Ofer Lahav  Ian Lewis  Stuart Lumsden  Darren Madgwick  John A. Peacock  Bruce A. Peterson  Ian Price  Mark Seaborne  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2001,328(4):1039-1063

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The chemical evolution of the atmosphere and oceans: By Heinrich D. Holland. Princeton Univ. Press,Princeton, N.J., 1984. pp., pb $24.50, hb $75.00     

John S. Lewis 《Icarus》1985,64(2):337

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Vector magnetic fields in prominences     

Lewis L. House  Raymond N. Smartt 《Solar physics》1982,80(1):53-69

A preliminary discussion is presented of measurements of the polarization of the He i D₃ multiplet in a quiescent prominence, observed with a wavelength-scanning Stokes polarimeter. For a series of 43 observations in the same prominence, the linear polarization of the major component of D₃ lies primarily in the range 1 to 2% and of the wing component, the range 2 to 5%; the polarization vector angle lies primarily in the range 10–25° for the major component, and 25–35° for the other component. From a more limited data set, the polarization of both components is found to first increase as a function of height in the prominence, and then to decrease; the polarization angles of the major component vary in a random-like way with height, while the wing component shows a systematic change. The amount of polarization and the angle of polarization are governed by the Hanle effect. The collective effect of the group of lines at the peak of D₃ evidently has a different sensitivity to the Hanle effect than does the wing component, thus yielding at least four independent measurements - two polarizations and two angles. With some redundancy, the vector magnetic field can then be established using the detailed theory of the Hanle effect. Since the wing component of D₃ is a simple triplet, an initial estimate of the magnetic field strength and its horizontal orientation, 0, relative to the line of sight, is simply obtained. Examples of such calculations are presented.The National Center for Atmospheric Research is sponsored by the National Science Foundation.Operated by the Association of Universities for Research in Astronomy, Inc. under contract AST 78-17292 with the National Science Foundation.  相似文献   

Fluid inclusions in high-grade gneisses of the Kapuskasing structural zone,Ontario: metamorphic fluids and uplift/erosion path     

Roberta L. Rudnick  Lewis D. Ashwal  Darrell J. Henry 《Contributions to Mineralogy and Petrology》1984,87(4):399-406

Fluid inclusions in quartz grains from five samples of high-grade rocks (two paragneisses, an amphibolite, a mafic gneiss and a tonalite dike) from the 2.7 Ga Kapuskasing structural zone (KSZ), Ontario, were examined with petrographic, microthermometric and laser Raman techniques. Three types of fluid inclusions were observed: CO₂-rich, H₂O-rich and mixed CO₂-H₂O. CO₂-rich fluid inclusions are pseudosecondary or secondary in nature and are generally pure CO₂; a few contain varying amounts of CH₄·H₂O-rich fluid inclusions are secondary in nature, contain variable amounts of dissolved salts, and generally contain daughter crystals. Mixed CO₂-H₂O fluid inclusions occur where trails of H₂O-rich inclusions intersect trails of CO₂-rich inclusions. Isochores for high density (p=1.03 g/cm³) pseudosecondary, pure CO₂ inclusions intersect the lower pressure portion of the estimated P-T field for high-grade metamorphism, implying that pure CO₂ was the peak metamorphic fluid. The variable CH₄ content of CO₂ inclusions within graphite-bearing samples suggests that CH₄ was introduced locally after the formation of the CO₂ inclusions; however the origin of the CH₄ remains problematic. An aqueous fluid clearly penetrated the gneisses after the peak metamorphism (during uplift/erosion), forming secondary inclusions and contributing to the minor retrogressive hydration observed in these rocks. The presence of the pseudosecondary, high-density CO₂ inclusions in quartz crystals in the KSZ rocks constrains the uplift/ erosion path for the KSZ to one of simultaneous decrease in pressure and temperature.  相似文献   

There is no horohalinicum     

Lewis E. Deaton  Michael J. Greenberg 《Estuaries and Coasts》1986,9(1):20-30

Species abundance declines to a minimum (the Artenminimum) between 5 and 8‰, not only in estuaries, but in all bodies of brackish water. Khlebovich (1968) examined published hydrochemical data for estuaries and concluded that sharp changes in the ionic composition of seawater diluted with fresh water occur at salinities below 5 to 8‰. He further argued that these ionic changes constitute a physico-chemical barrier between marine and freshwater faunas. Kinne (1971) gave the name “horohalinicum” to the segment of the salinity gradient between 8 and 5‰. We have re-examined the data used by Khlebovich (1968) and found that, in fact, while the ionic composition of diluted seawater changesslightly between 8 and 5‰, the changes in ionic ratios below 2‰ are much larger. Thus, the proposed physico-chemical barrier does not exist between 8 and 5‰; it cannot then explain the Artenminimum; and there is no basis for the horohalinicum concept of Kinne (1971). Two ecological explanations for the occurrence of the Artenminimum—a species-area effect and the stability-time hypothesis—are discussed and found to be inconsistent with published data on species distributions in brackish waters. The low species diversity of brackish water may be explained, in part, by two factors: few animals evolve those physiological mechanisms required for life in the variable habitat; and these species, which are very eurytopic, have low rates of speciation.  相似文献   

Comments on a paper by V.M. Oversby and A.E. Ringwood (Earth Planet. Sci. Letters 14 (1972) 345–347)     

Kenneth A. Goettel  John S. Lewis 《Earth and Planetary Science Letters》1973,18(1):148-150

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Noble gas abundance patterns in deep-sea basalts — Primordial gases from the mantle     

Jack Dymond  Lewis Hogan 《Earth and Planetary Science Letters》1973,20(1):131-139

Rapidly cooled portions of eleven samples of mid-ocean ridge tholeiitic basalt pillows have noble gas abundance patterns which resemble the solar rare gas pattern rather than the noble gas pattern of the terrestrial atmosphere. We conclude that these samples contain primordial noble gases. In contrast, holocrystalline samples and a sample from the interior of a basalt pillow have noble gas abundance patterns which resemble the sea water pattern. Whereas the quenched glossy margins of basalt pillows record a non-atmospheric gas reservoir, these slowly cooled samples apparently have undergone exchange of their noble gases with those dissolved in sea water.  相似文献