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971.
State formation and nation-building in the Netherlands and the Soviet Union: a historical comparison
Hans Knippenberg 《GeoJournal》1996,40(3):249-262
The interrelated processes of state formation and nation-building are analysed for two cases: the Netherlands (1795–1960) and the Soviet Union (1917–1989). The central question is: how did these states deal with strong cultural (religious or ethnic) cleavages in its societies. In general, there are three options: elimination marginalization, and institutionalization. In both states institutionalization was dominant, but the kind of institutionalization differed very much: personalistic (the Netherlands) versus territorial (Soviet Union) institutionalization. The hypothesis has been put forward that, in general, institutionalization on a personalistic basis will create more political stability. 相似文献
972.
A resume of the main results obtained in the framework of fast electron hypothesis is presented. The fast electrons are possessed by strong constant properties, that is, nearly monoenergetic in spectrum and with the energy of 3. Fast electrons appear spontaneously in all kinds of cool dwarfs, young and old, and stimulate the generation of all types of flares, faint and powerful, in all ranges of electromagnetic waves — optical, ultraviolet, radio, X-ray. The general flare mechanisms are inverse Compton effect at the faint and moderate flares and nonthermal bremsstrahlung at powerfulness. This hypothesis explains an enormous number of observational facts and relationships — all these are illustrated by two tree-like diagrams in Figures 1 and 2.In the second part, the problem of the spontaneous appearance of fast electrons above the stellar atmosphere is discussed. The nature of the fast electrons in universal and is independent of the physical conditions of the star or its atmosphere. Their origin have nothing in common also with the well known acceleration processes, including the magnetic and hydrodynamic nature, in stellar atmospheres. At present nuclear decay processes seem to be most probable for the appearance of fast electrons in outer regions of stellar atmospheres. Some decay processes are examined with various probability of their realization. Creation of the radioactive nucleus13N as a result of capture of H by12C and its consequent decay with the escape of a positron seems most probable; as this fast positron will act just like a fast electron. It is outlined the high effectivity of this process in binary systems. 相似文献
973.
We have studied two congeneric limid bivalves, Acesta species novum and Acesta excavata (Bivalvia: Limidae), that live in similar physical conditions but use different food sources. Acesta sp. nov. live on the giant siboglinid tubeworm Lamellibrachia luymesi at cold seeps and feed on their eggs, a continuous food source that ultimately is derived from chemosynthesis, whereas A. excavata relies on planktonic food of photosynthetic origin, which varies seasonally. We hypothesized that these two species might show differences in the periodicity of reproduction; specifically, we predicted that A. sp. nov. would breed continuously and that A. excavata would demonstrate an annual reproductive cycle. Our hypothesis was refuted, as both species have a semi‐continuous reproductive cycle. Food quality, quantity or seasonality had no clear effect. Reproductive adults are functionally gonochoristic. Females broadcast buoyant eggs with an average size of 179 μm in A. sp. nov. and 160 μm in A. excavata. Both the size of the larval shell and the size of the spawned eggs are suggestive of pelagic lecithotrophic development. Both species also appear to be protandric hermaphrodites, changing from male to female at approximately 77 and 90 mm shell height, respectively, although not all individuals change sex. In the material investigated in this study there was a biased sex ratio favouring males. 相似文献
974.
The concentrations of Pb, Cu, Cd and Zn were determined in above- and belowground parts of eelgrass (Zostera marina L.) at forty stations in a shallow, brackish water area (the Limfjord, Denmark). The concentrations of the trace metals were significantly elevated near the cities of Aalborg (Pb, Cu) and Struer (Cd). Trace metal concentrations in above and belowground parts of eelgrass were log-normal distributed and the concentrations of Cd, Cu and Zn in aboveground parts were significantly higher than in belowground parts. Furthermore, a significant correlation between trace metal concentrations in above- and belowground parts was found. The background level of trace metal concentrations in eelgrass in the Limfjord was estimated.The application of eelgrass as a monitoring organism is discussed; it is suggested that the concentration of some trace metals in above- and belowground parts of eelgrass may be used as a measure of the bioavailable fraction of these trace metals in ambient and interstitial water (sediment), respectively. 相似文献
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978.
Sedimentary,tectonic, and sea-level controls on submarine fan and slope-apron turbidite systems 总被引:1,自引:0,他引:1
To help understand factors that influence submarine fan deposition, we outline some of the principal sedimentary, tectonic, and sea-level controls involved in deep-water sedimentation, give some data on the rates at which they operate, and evaluate their probable effects. Three depositional end-member systems, two submarine fan types (elongate and radial), and a third nonfan, slope-apron system result primarily from variations in sediment type and supply. Tectonic setting and local and global sea-level changes further modify the nature of fan growth, the distribution of facies, and the resulting vertical stratigraphic sequences. 相似文献
979.
C. Hans Nelson Andres Maldonado Francis Coumes Henri Got Andre Manaco 《Geo-Marine Letters》1983,3(2-4):125-131
The Ebro Fan System consists of en echelon channel-levee complexes, 50×20 km in area and 200-m thick. A few strong reflectors in a generally transparent seismic facies identify the sand-rich channel floors and levee crests. Numerous continuous acoustic reflectors characterize overbank turbidites and hemipelagites that blanket abandoned channel-levee complexes. The interlobe areas between channel complexes fill with homogeneous mud and sand from mass flow and overbank deposition; these exhibit a transparent seismic character. The steep continental rise and sediment “drainage” of Valencia Trough at the end of the channel-levee complexes prevent the development of distributary channels and midfan lobe deposits. 相似文献
980.
This is a paper from the Swedish research project ‘The coastal zone—scientific criteria for planners’. The goal has been to establish simple, general scientific methods for management of Swedish coastal waters. In this paper the focus is on a set of empirical data from 21 so-called type areas and on the exchange of surface water. The working hypothesis has been that the water retention (or residence) time is regulated by the morphometry. The theory has been verified. It has been shown that the water retention time can be determined from a formula based on only two key morphometric parameters, the exposure and the mean coastal width. It provides an 86% degree of explanation (r2=0·86) of the variation in empirically determined retention times and can be physically linked to the basic mass balance equation. The formula is valid for the bioproductive season (May–Oct.) and for small (1–100 km2) Swedish coastal areas. It cannot be directly applied to areas affected by heavy tides. 相似文献