H ii and H₂ in the envelopes of cooling flow central galaxies     

W. Jaffe  M. N. Bremer  K. Baker 《Monthly notices of the Royal Astronomical Society》2005,360(2):748-762

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Fundamental galaxy parameters for radio-loud active galactic nuclei and the black hole–radio power connection     

I. A. G. Snellen  M. D. Lehnert  M. N. Bremer  R. T. Schilizzi 《Monthly notices of the Royal Astronomical Society》2003,342(3):889-900

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A quasar in a compact group of galaxies at  z= 0.7      

M. N. Bremer  Joanne C. Baker †  Matthew D. Lehnert 《Monthly notices of the Royal Astronomical Society》2002,337(2):470-476

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Book reviews     

Richard J. Reed  Hanna J. Cortner  Peter M. Morrisette  A. J. Pitman 《Climatic change》1990,16(3):357-366

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Foucault,sustainable tourism,and relationships with the environment (human and nonhuman)     

Paul Hanna  Katherine Johnson  Paul Stenner  Matt Adams 《GeoJournal》2015,80(2):301-314

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Hydrothermal jarosite and hematite in a pyroxene-hosted melt inclusion in martian meteorite Miller Range (MIL) 03346: Implications for magmatic-hydrothermal fluids on Mars     

Francis M. McCubbin  Nicholas J. Tosca  Hanna Nekvasil  Marc Fries  Donald H. Lindsley 《Geochimica et cosmochimica acta》2009,73(16):4907-318

Low-temperature aqueous processes have been implicated in the generation of jarosite and hematite on the martian surface, but little is known regarding the role that high-temperature magmatic fluids may have played in producing similar assemblages on Mars. We have identified jarosite and hematite in a clinopyroxene-hosted melt inclusion in martian meteorite MIL 03346 that shows evidence of having been hydrothermally precipitated. In addition to jarosite and hematite, the melt inclusion contains titanomagnetite, pyrrhotite, potassic-chlorohastingsite, an iron-rich silicate glass and possibly goethite. These phases were identified and characterized using scanning electron microscopy (SEM), con-focal Raman-spectroscopy and electron probe microanalysis (EPMA).Based on observed textural relationships and the compositions of the hosted phases, we report that the jarosite-bearing melt inclusion in MIL 03346 has recorded a fluid-rich history that began in the magmatic stage and continued to low-temperatures. This history begins at entrapment of a volatile-rich silicate melt that likely reached fluid-saturation after only minor crystallization within the melt inclusion. This fluid, rich in chlorine, reacted with surrounding silicate material to produce the potassic-chlorohastingsite. As cooling proceeded, the liquid phase eventually became more oxidized and reacted with the pyrrhotite. Sulfide oxidation resulted in SO₄²⁻ formation and concomitant acid production, setting the stage for jarosite formation once the fluid cooled beyond the upper thermal stability of jarosite (∼200 °C). As the fluid cooled below 200 °C, jarosite continued to precipitate with hematite and/or goethite until equilibrium was established or reactions became kinetically unfavorable.This work suggests an additional jarosite-hematite formation pathway on Mars; one that may be important wherever magmatic-hydrothermal fluids come into contact with primary sulfide grains at the martian surface or subsurface. Moreover, hydrothermal fluids rich in chlorine, sulfur, and iron are important for ore-forming processes on Earth, and their indirect identification on Mars may have important implications for ore-formation on Mars.  相似文献   

YORP torque as the function of shape harmonics     

S&#;awomir Breiter  Hanna Michalska 《Monthly notices of the Royal Astronomical Society》2008,388(2):927-944

The second-order analytical approximation of the mean Yarkovsky–O'Keefe–Radzievskii–Paddack (YORP) torque components is given as an explicit function of the shape spherical harmonics coefficients for a sufficiently regular minor body. The results are based upon a new expression for the insolation function, significantly simpler than in previous works. Linearized plane-parallel model of the temperature distribution derived from the insolation function allows us to take into account a non-zero conductivity. Final expressions for the three average components of the YORP torque related with rotation period, obliquity and precession are given in a form of the Legendre series of the cosine of obliquity. The series have good numerical properties and can be easily truncated according to the degree of the Legendre polynomials or associated functions, with first two terms playing the principal role.  相似文献   

新的加利福尼亚地震动日常概率地图     

S．Hanna M．Gerstenberger W．Shindle蒋长胜  张天中 《国际地震动态》2005,(6):1-2

美国地质调查局(USGS)5月18日宣布开放一个可显示加州地区未来24小时内发生地震概率的公共网站。在余震或可能的前震序列期间,它以地图的形式向人们展示地震发生概率的变化。  相似文献   

Egyptian cotton (Gossypium barbadense) flower and boll production as affected by climatic factors and soil moisture status     

Zakaria M. Sawan  Louis I. Hanna  Willis L. McCuistion  Richard J. Foote 《Theoretical and Applied Climatology》2010,99(1-2):217-227

The information on impact of climatic factors on cotton production is not generally available, or at least not available in the required form. Understanding this impact may help physiologists determine a possible control of the flowering mechanism in the cotton plant. Two field trials were conducted to investigate the relationships between climatic factors, soil moisture status, and flower and boll production of Gossypium barbadense. The climatic factors considered were daily maximum air temperature (°C), minimum air temperature (°C), maximum–minimum temperature (diurnal temperature range) (°C), sunshine duration (h day^?1), maximum relative humidity (%), minimum relative humidity (%), and wind speed (m s^?1). Minimum relative humidity and sunshine duration were the most significant climatic factors affecting flower and boll retention and production. Temperature appeared to be less important in the reproduction growth stage of cotton in Egypt than minimum relative humidity and sunshine duration. The soil moisture status showed low and insignificant correlation to flower and boll production. High minimum relative humidity, short period of sunshine duration, and low temperatures enhanced flower and boll formation.  相似文献   

Derivation and test of ionospheric activity indices from real-time ionosonde observations in the European region   总被引：1，自引：0，他引：1  

J. Bremer  Lj.R. Cander  J. Mielich  R. Stamper 《Journal of Atmospheric and Solar》2006,68(18):2075-2090

New ionospheric activity indices are derived from automatically scaled online data from several European ionosonde stations. These indices are used to distinguish between normal ionospheric conditions expected from prevailing solar activity and ionospheric disturbances caused by specific solar and atmospheric events (flares, coronal mass ejections, atmospheric waves, etc.). The most reliable indices are derived from the maximum electron density of the ionospheric F 2-layer expressed by the maximum critical frequency foF 2. Similar indices derived from ionospheric M(3000)F 2 values show a markedly lower variability indicating that the changes of the altitude of the F 2-layer maximum are proportionally smaller than those estimated from the maximum electron density in the F 2-layer. By using the ionospheric activity indices for several stations the ionospheric disturbance level over a substantial part of Europe (34°N–60°N; 5°W–40°E) can now be displayed online.  相似文献