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81.
Nelson D. Padilla Carlton M. Baugh Vincent R. Eke Peder Norberg Shaun Cole Carlos S. Frenk Darren J. Croton Ivan K. Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick John A. Peacock Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2004,352(1):211-225
82.
Boris T. Gäansicke Domitilla De Martino Thomas R. Marsh Carole A. Haswell Christian Knigge Knox S. Long Steven N. Shore 《Astrophysics and Space Science》2006,303(1-4):53-68
Interacting Binaries consist of a variety of stellar objects in different stages of evolution and those containing accreting compact objects still represent a major challenge to our understanding of not only close binary evolution but also of the chemical evolution of the Galaxy. These end-points of binary star evolution are ideal laboratories for the study of accretion and outflow processes, and provide insight on matter under extreme physical conditions. One of the key-questions of fundamental relevance is the nature of SN Ia progenitors. The study of accreting compact binary systems relies on observations over the entire electromagnetic spectrum and we outline here those unresolved questions for which access to the ultraviolet range is vital, as they cannot be addressed by observations in any other spectral region.An erratum to this article can be found at 相似文献
83.
Darren S. Madgwick Ed Hawkins Ofer Lahav Steve Maddox Peder Norberg John A. Peacock Ivan K. Baldry Carlton M. Baugh Joss Bland-Hawthorn Terry Bridges Russell Cannon Shaun Cole Matthew Colless Chris Collins Warrick Couch Gavin Dalton Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Carlos S. Frenk Karl Glazebrook Carole Jackson Ian Lewis Stuart Lumsden Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2003,344(3):847-856
84.
Manuela Magliocchetti Steve J. Maddox Carole A. Jackson Joss Bland-Hawthorn Terry Bridges Russell Cannon Shaun Cole Matthew Colless Chris Collins Warrick Couch Gavin Dalton Roberto de Propris Simon P. Driver George Efstathiou Richard S. Ellis Carlos S. Frenk Karl Glazebrook Ofer Lahav Ian Lewis Stuart Lumsden John A. Peacock Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2002,333(1):100-120
85.
We present major and trace element data of five glass cosmic spherules (CS) with differentiated compositions recovered in the South Pole Water Well and the Transantarctic Mountains, Antarctica. The differentiated CS were first identified using Fe/Mg and Fe/Mn ratios and we have now added high Rare Earth Element concentrations (5 < REEN < 14), and low siderophile element abundances (e.g. Ni = 25 ± 27 ppm) as characteristics. We propose that the siderophile depletions observed in differentiated CS result from the segregation of these elements into the core of their parent body during differentiation. Then, the high Fe/Mg ratios of differentiated CS result from their low MgO contents. Combined with their high level of REE enrichment, this indicates that the precursors formed through basaltic melt extraction from the asteroid/planetary source. As Fe/Mn and Fe/Mg ratios cannot distinguish between a Martian or Vestoid origin, we measured trace elements (zinc, cobalt, and vanadium) whose chemical behavior depends on oxidation state, known to be higher in the Martian than in the Vestoid environment. The compositions of the differentiated CS studied in this work share the characteristics of eucrites for all these indicators, providing further evidence that these differentiated CS are samples of a Vesta-like asteroid. However, their precursors show a considerable diversity in their mineralogy when compared to eucrites, that results in a wider range of major (Ca and Al) and trace element (Ba, Sr, Sc, and V) composition in differentiated CS. 相似文献
86.
87.
Lincoln R. Larson Caren B. Cooper Richard C. Stedman Daniel J. Decker Ryan J. Gagnon 《社会与自然资源》2018,31(8):871-891
This study expands existing models of proenvironmental behavior (PEB) to examine the potentially important and interacting influences of nature-based recreation and sense of place on participation in conservation-oriented activities. We tested hypothesized relationships using a structural equation modeling approach that accounted for common behavioral antecedents within a sample of 1,124 nature-based recreationists and property owners in rural counties of New York, USA. We found that place attachment played an important role in strengthening connections between nature-based recreation and PEB. Birdwatching and hunting participation contributed independently and significantly to PEB, both directly and indirectly through effects on place meanings and place attachment. While birdwatching appeared to influence place attachment by impacting environmental place meanings, hunting exerted similar effects by affecting sociocultural place meanings. Ultimately, our synthesis results in the articulation of a comprehensive conservation–recreation model that could help researchers and practitioners identify and explore novel pathways to PEB. 相似文献
88.
Lukas Plan Kurt Decker Robert Faber Michael Wagreich Bernhard Grasemann 《Environmental Geology》2009,58(2):285-297
High alpine karst plateaus are recharge areas for major drinking water resources in the Alps and many other regions. Well-established
methods for the vulnerability mapping of groundwater to contamination have not been applied to such areas yet. The paper characterises
this karst type and shows that two common vulnerability assessment methods (COP and PI) classify most of the areas with high
vulnerability classes. In the test site on the Hochschwab plateau (Northern Calcareous Alps, Austria), overlying layers are
mostly absent, not protective or even enhance point recharge, where they have aquiclude character. The COP method classifies
82% of the area as highly or extremely vulnerable. The resulting maps are reasonable, but do not differentiate vulnerabilities
to the extent that the results can be used for protective measures. An extension for the upper end of the vulnerability scale
is presented that allows identifying ultra vulnerable areas. The proposed enhancement of the conventional approach points out that infiltration conditions are of key importance
for vulnerability. The method accounts for karst genetical and hydrologic processes using qualitative and quantitative properties
of karst depressions and sinking streams including parameters calculated from digital elevations models. The method is tested
on the Hochschwab plateau where 1.7% of the area is delineated as ultra vulnerable. This differentiation could not be reached
by the COP and PI methods. The resulting vulnerability map highlights spots of maximum vulnerability and the combination with
a hazard map enables protective measures for a manageable area and number of sites. 相似文献
89.
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