UNDERGROUND WATERS NOW UNDEVELOPED     

Stewart L. Udall 《Ground water》1967,5(4):2-5

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Relativistically induced instellar density fluctuations     

P. Stewart 《Astrophysics and Space Science》1973,24(1):269-277

The spectrum of cold electron density fluctuations induced by a relativistic electron gas is investigated and the results discussed in relation to the interstellar medium.  相似文献   

Aleutian Strain Events: Observations and Interpretation     

J. H. Pfluke  R. M. Stewart 《Geophysical Journal International》1973,35(1-3):229-241

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Evolution of Planetesimal Velocities Based on Three-Body Orbital Integrations and Growth of Protoplanets     

Keiji OhtsukiGlen R. Stewart  Shigeru Ida 《Icarus》2002,155(2):436-453

We obtain the viscous stirring and dynamical friction rates of planetesimals with a Rayleigh distribution of eccentricities and inclinations, using three-body orbital integration and the procedure described by Ohtsuki (1999, Icarus137, 152), who evaluated these rates for ring particles. We find that these rates based on orbital integrations agree quite well with the analytic results of Stewart and Ida (2000, Icarus 143, 28) in high-velocity cases. In low-velocity cases where Kepler shear dominates the relative velocity, however, the three-body calculations show significant deviation from the formulas of Stewart and Ida, who did not investigate the rates for low velocities in detail but just presented a simple interpolation formula between their high-velocity formula and the numerical results for circular orbits. We calculate evolution of root mean square eccentricities and inclinations using the above stirring rates based on orbital integrations, and find excellent agreement with N-body simulations for both one- and two-component systems, even in the low-velocity cases. We derive semi-analytic formulas for the stirring and dynamical friction rates based on our numerical results, and confirm that they reproduce the results of N-body simulations with sufficient accuracy. Using these formulas, we calculate equilibrium velocities of planetesimals with given size distributions. At a stage before the onset of runaway growth of large bodies, the velocity distribution calculated by our new formulas are found to agree quite well with those obtained by using the formulas of Stewart and Ida or Wetherill and Stewart (1993, Icarus106, 190). However, at later stages, we find that the inclinations of small collisional fragments calculated by our new formulas can be much smaller than those calculated by the previously obtained formulas, so that they are more easily accreted by larger bodies in our case. The results essentially support the previous results such as runaway growth of protoplanets, but they could enhance their growth rate by 10-30% after early runaway growth, where those fragments with low random velocities can significantly contribute to rapid growth of runaway bodies.  相似文献   

Editorial     

John Wilson  Stewart Fotheringham  Gary Hunter  Jochen Albrecht 《Transactions in GIS》2006,10(2):153-153

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Ten Years On . . .     

John Wilson  Stewart Fotheringham  Gary Hunter  Jochen Albrecht 《Transactions in GIS》2006,10(3):333-333

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A method for generating uniform size-segregated pyrite particle fractions     

Amy L Wolfe  Ran Liu  Brian W Stewart  Rosemary C Capo  David A Dzombak 《Geochemical transactions》2007,8(1):9

Background  

Standardized sample preparation techniques allow comparison of pyrite dissolution experiments under diverse conditions. Our objective was to assess dry and wet sieving preparation methodologies, and to develop a reproducible technique that yields uniformly size-distributed material within a limited size range of interest.  相似文献   

Tsunami deposits in the geological record   总被引：2，自引：0，他引：2  

Alastair G. Dawson  Iain Stewart 《Sedimentary Geology》2007,200(3-4):166-183

A review is presented here of tsunami deposits in the geological record. It begins with a discussion of the relationships between the processes of tsunami generation and propagation and the sedimentary responses. This is followed by a consideration of the sedimentary processes associated with the passage of tsunami waves across coastlines. Attention is also given to the sedimentary processes associated with tsunami-triggered gravity backwash flows and comparisons are made with turbidity current action. We observe that despite sedimentary evidence for recent tsunamiites, geological research on ancient tsunamis has not identified stratigraphic units associated with onshore tsunami sedimentation. Equally, it is noted that nearly all published studies of sedimentary processes associated with modern tsunamis have not considered patterns of sediment transport and deposition in the offshore zone.  相似文献   

The Varying Multipolar Structure of the Sun's Magnetic Field and the Evolution of the Solar Magnetosphere Through the Solar Cycle     

Bravo  S.  Stewart  G. A.  Blanco-Cano  X. 《Solar physics》1998,179(2):223-235

The Sun's magnetic field extends far from the photosphere, into the corona, defining a magnetically dominated region before being drawn out radially by the solar wind flow. This region, where the internal sources of the solar field dominate the plasma structures and the energetic particle movement, can be properly considered the solar magnetosphere. The magnetic field in this region can be approximately described by models that extrapolate photospheric magnetic field observations under some simplifying assumptions. In this paper we use a potential field model which describes the solar field up to a source surface at 3.25 R_s, where the field is constrained to become radial. We present the variation of the magnitude and inclination of the various multipolar components throughout the solar magnetic cycle that characterise the changes in the structure of the solar magnetosphere over a period of 22 years. We also present some 3-D images of the coronal magnetic structure to show the global evolution of the solar magnetosphere throughout the solar cycle and discuss the importance of taking this structure into account in order to relate interplanetary and solar features.  相似文献   

The Deutsch field gamma-ray pulsar – II. Application of the model     

M. G.Higgins  R. N.Henriksen 《Monthly notices of the Royal Astronomical Society》1998,295(1):188-196

A new model for gamma-ray pulsars presented by Higgins & Henriksen is applied to the cases of the seven known gamma-ray pulsars. Those pulsars that are not presently observed in gamma-rays, but are candidates for observation by the next generation of gamma-ray telescopes, are discussed. The case of millisecond pulsars is discussed, and it is shown that these objects should radiate at detectable levels, in opposition to the predictions of other gamma-ray pulsar models.  相似文献