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31.
On the basis of the newest interpretations of all sufficiently long seismic profiles, a contour map of the Mohorovi?i? discontinuity for the conterminous United States is compiled. Differences from earlier interpretations are discussed. 相似文献
32.
WORLD DELTAS AND THEIR EVOLUTION 总被引:1,自引:0,他引:1
H. Jesse Walker 《地理学报》1999,(1):30-41
In August 1998, an international symposium on the world deltas was held in New Orleans, Louisiana, USA. This symposium attracted discussion about more than 25 deltas from around the world with emphasis placed on those that are most densely populated and impacted by humans. Keynote papers printed details about the physical, biological, engineering and socioeconomic aspects of six deltas including the Mississippi, Nile, Ganges-Brahmaputra, Rhine-Meuse, Changjiang and Po. The main purpose of this symposium was to inform scientists, engineers and decision-makers about information that is currently available and to provide them a basis for working in such environments. 相似文献
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Warren G. Heller 《Journal of Geodesy》1981,55(4):354-369
The state of current and proposed moving-base gravity gradiometer instruments is briefly reviewed. The review perspective is directed toward their deployment as a source of additional gravimetric data during inertial surveys. In such gradiometer-aided surveys, the additional gravity gradient information could be used to:
- Improve surveyed gravity vector accuracy
- Extend the interval between zero velocity update stops
- Accomplish varying combinations of the above.
35.
The review is in three main sections. First, the observation that overall flotation performance deteriorates for the finest particles is confirmed, but the precise effects of particle size on recovery, grade, and flotation rate are shown to be more complex. In the second section an assessment is made of theories which have been proposed to explain the slower flotation rate of ultrafines, the effects of slime coating, and the flotation of slimes with cationic collectors. The last section of the paper gives a critical evaluation of methods which are claimed to improve the flotation of ultrafine particles. 相似文献
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Eric Huff A.E. Schulz Martin White David J. Schlegel Michael S. Warren 《Astroparticle Physics》2007,26(6):351-366
The coupling of photons and baryons by Thomson scattering in the early universe imprints features in both the cosmic microwave background (CMB) and matter power spectra. The former have been used to constrain a host of cosmological parameters, the latter have the potential to strongly constrain the expansion history of the universe and dark energy. Key to this program is the means to localize the primordial features in observations of galaxy spectra which necessarily involve galaxy bias, non-linear evolution and redshift space distortions. We present calculations, based on mock catalogs produced from high-resolution N-body simulations, which show the range of behaviors we might expect of galaxies in the real universe. We investigate physically motivated fitting forms which include the effects of non-linearity, galaxy bias and redshift space distortions and discuss methods for analysis of upcoming data. In agreement with earlier work, we find that a survey of several Gpc3 would constrain the sound horizon at z 1 to about 1%. 相似文献
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Alan Warren 《中国海洋大学学报(英文版)》2009,8(4):317-321
The morphology and infraciliature of a new marine colepid ciliate, Apocoleps magnus gen. nov., spec. nov., are described based on living observations and silver impregnations. The new genus Apocoleps is characterized by having 8 (vs. 6 in most other related genera) armour tiers, spines at both ends of the cell, 3 adoral organelles and plates with 4 reniform uni-windows. Apocoleps magnus spec. nov. is defined by the following features: body elongated and slightly curved, about 100–120μm× 35–45 μm in vivo; an... 相似文献
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