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251.
Marine resource development has increased its importance for most of the world's coastal nations. This is especially true for developing coastal states that are now looking to the sea to help provide new sources of food and income. Belize is an example of such a developing state with certain features that make it particularly interesting for study.  相似文献   
252.
In this study we made a comparative interpretation of multibeam bathymetric and seismic reflection data with different resolutions and penetration properties collected in the Central Basin of the Marmara Sea. Our main objectives were (i) to investigate and compare the active tectonic deformation observed on the sea bottom and within the uppermost sedimentary layers to that of the deep-seated deformation within the limits of resolution and penetration of the available geophysical data and (ii) to build a three-dimensional (3D) block diagram of the active tectonic and buried features by means of a sliced mapping technique. In this approach, we produced slice maps of the active and buried structural features at selected depths and then combined them to form a 3D structural block diagram. Motivation for our work was to produce a 3D structural diagram to derive a more detailed image of the structural features in the Central Basin where there is no available 3D seismic data. The observations from the bathymetry and seismic data and developed 3D diagram support the presence of a through-going strike-slip fault that forms a rotational depression zone against a right-stepping strike-slip faulting causing a pull-apart basin in the Central Depression zone.  相似文献   
253.
A central part of the GRB 790613 field is investigated, which contains about 1/3 of the area of 99% confidence of the GRB localization. Up to V 25 no blue optical counterparts were found. This can be interpreted as the absence in the field of single compact objects of the neutron star type as a possible potential source of -burst, up to a distance of 30 pc.  相似文献   
254.
Temporal and spatial variation in soft‐bottom benthic communities following recovery from a pollution episode were studied between January and September 2004 in and around Alsancak Harbor, located in the polluted part of Izmir Bay (Aegean Sea, eastern Mediterranean). Samples were collected at seven stations by van Veen grab. Three additional stations were sampled by means of a beam trawl to take into account large mobile animals and for a better estimate of the local biodiversity. A total of 231 species belonging to 10 zoobenthic groups were found. Polychaetes contributed 90% of the total faunal populations and mollusks 87% of the total biomass in the area. Community parameters varied significantly among stations and sampling periods; number of species ranged from 2 to 79 per 0.1 m2 grab sample; density from 20 to 81,720 ind·m?2; biomass from 0.1 to 4190 g·m?2; Shannon–Wiener diversity index (log2 base) from 0.4 to 4.4; and Pielou's evenness index from 0.11 to 1.0. Collections indicate that a number of species, including those sensitive to pollution, have colonized the area where azoic conditions had been previously reported. A total of six exotic species, Streblospio gynobranchiata, Polydora cornuta, Hydroides dianthus, Hydroides elegans, Anadara demiri and Fulvia fragilis, probably transferred to the area via ballast water or hull fouling, dominated soft or hard substrata in and near Alsancak Harbor. The first two species accounted for more than 70% of the total population in the area, while A. demiri contributed the most to the biomass (93%, at station 7).  相似文献   
255.
Abstract. Species' depth distributions and abundances were visually assessed along 24 transects in a northern Adriatic assemblage of blennioid fishes (14 species of Blenniidae , 1 species of Triptery-giidue). Total abundance of blennioids was highest in 0.5-1 m depth, decreasing upwards and downwards. Species diversity (S hannon -W iener ) is highest at the shallowest depth (0-0.5 in). The curybathic species Parablennius incognitus, Lipophrys dalmatinus, Tripterygion tripteronotus , and Parablennius tentacularis were most abundant at all depths (relative to the species investigated). All stenobathic species were most abundant at 0-0.5 m. Depth distribution patterns and abundance ranks of species were similar at western, eastern, southern, and northern transects.  相似文献   
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Zusammenfassung Einige einfache Beziehungen zwischen den Schwere-Werten und der Formung der Gebirge werden gezeigt.
Summary Some simple relations between the formation of the mountains and the gravity are discussed.
  相似文献   
259.
Zusammenfassung Auf der Grundlage der Hansen-Schumacherschen Kippthermometertabellen werden vier Fluchtentafeln entworfen, deren Vorzüge in ihrer besonders schnellen Herstellungsweise, ihrer einfachen und zeitersparenden Anwendungsweise und ihrem verhältnismäßig geringen Raumbedarf bestehen.
Nomograms for correcting the readings of reversible thermometers
Summary Basing on correction tables for reversible thermometers after Hansen-Schumacher four nomograms are designed which are characterized by their particularly quick way of establishment, their simple and time-saving way of employment and the comparatively small space required.

Nomogrammes pour corriger les indications de thermomètres à renversement
Résumé Quatre nomogrammes sont présentés qui s'appuient sur les tables de correction pour les thermomètres à renversement d'après Hansen-Schumacher. Ces nomogrammes sont signalés par leur mode particulièrement rapide d'établissement et par leur simplicité et vitesse d'emploi; de plus, ils sont peu encombrants.
  相似文献   
260.
Summary Two determination of the sun's temperatur by application of the law ofWien on 2 published bolometer-curves of the Astrophysical Observatory, Washington.  相似文献   
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