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101.
102.
The impact of domestic sewage effluent (SE) on the dynamics of phytoplankton assemblages from Bedford Basin was evaluated in the laboratory. Phytoplankton production and chlorophyll a increased proportionally with SE enrichment. Phytoplankton species composition also changed. The potentially harmful diatoms, Pseudonitzschia spp., present initially in small numbers (600 cells 1−1) in Bedford Basin seawater, and became dominant (3–5×106 cells 1−1) when the seawater was enriched with 0.5–5% untreated SE. With higher proportions of SE, other harmful species such as Fragilaria spp. and Euglena spp. became dominant (7−15×106 and 2.2×104 cells 1−1, respectively). Treatment of SE with UV light or activated charcoal seems to favour growth of benign species, such as Chaetoceros socialis, Skeletonema costatum and Thalassiosira spp., but not harmful species such as Pseudonitzschia spp. Further research on UV treatment of domestic sewage is recommended.  相似文献   
103.
Characteristics of the current state of transportation problems along the Northern Sea Route are given. The required ice data necessary to guarantee the safety of navigation are discussed. A variety of developing transportation prospects along the Northern Sea Route, including international aspects, are disputed. Effective economic alternatives of the Northern Sea Route under the conditions of the current Russian economic crisis are analyzed.  相似文献   
104.
Izvestiya, Atmospheric and Oceanic Physics - On the basis of calculations of insolation and insolation characteristics, taking into account changes in solar activity, the causes of global climatic...  相似文献   
105.
Short‐finned wild eels fed an artificial diet containing either a low (5%) or a high (20%) oil content were found to increase their mass by an average of more than 30% after a 34‐day feeding period; the lipid content of the eels’ muscle was also increased from about 10% to around 20%.  相似文献   
106.
This paper examines those aspects of reflection seismology which require special consideration when imaging deeper hydrocarbon reservoirs, including the constraints imposed by vertical resolution, lateral resolution, and velocity analysis. We derive quantitative expressions relating the uncertainties in stacking velocities and in interval velocities derived from stacking velocities to acquisition parameters, as well as expressions for the lateral resolution which can theoretically be achieved for migrated seismic images. This analysis shows that the most significant limitations of seismic imaging at depth involve the finite lateral resolution of the seismic method, and the proper lateral positioning of seismic images. These difficulties are overcome in large measure through the proper migration of a seismic dataset, which becomes more critical as deeper horizons are imaged. If these horizons are suspected of having significant 3-D structure, a strong argument may be made for acquiring a 3-D seismic survey over the prospect. Migration of this dataset will then generate an image of the subsurface with good lateral resolution in both the X and Y directions.  相似文献   
107.
The Vorochistoozersky, Nizhnepopovsky, and Severo-Pezhostrovsky gabbro-anorthosite massifs have been studied in the central part of the Belomorian Province, Fennoscandian Shield. The similarity of geological setting and rock composition of these massifs suggests their affiliation to a single complex. The age of the gabbro-anorthosites was determined by U-Pb (SHRIMP II) zircon dating of gabbro-pegmatites from the Vorochistoozersky massif at 2505 ± 8 Ma. The studied massifs were overprinted by the high-pressure amphibolite facies metamorphism. Relicts of magmatic layering and primary magmatic assemblages preserved in the largest bodies. The massifs consist mainly of leucocratic gabbros but also contain rocks of the layered series varying in composition from olivinite to anorthosite. The presence of troctolites in the layered series indicates the stability of the olivine–plagioclase liquidus assemblage and, respectively, shallow depths of melt crystallization. Despite the composition differences between gabbro-anorthosites of the Belomorian and peridotite–gabbronorite intrusions Kola provinces, these simultaneously formed massifs presumably mark a single great igneous event. It also includes the gabbronorite dikes in the Vodlozero terrane of the Karelian province, the Mistassini swarm in the Superior province, and the Kaminak swarm in the Hearne Craton, Canadian Shield. The large igneous province of age ~2500 Ma reflects the oldest stage of within-plate magmatism after a consolidation of the Neoarchean crust of the Kenorland Supercontinent (Superia supercraton).  相似文献   
108.
The study area is located in the central part of the Eastern Desert of Egypt and is mainly covered by different varieties of Precambrian basement rocks represented mainly by younger and older granites, metadiorite, metavolcanics, and metasediments. The analysis and interpretation of airborne gamma-ray spectrometric survey data are essentially based on the computation of the three radioelements (U, Th, and K) favorability indices, estimation of uranium migration rate percentage, variation of eU with eTh and eU/eTh ratio, and the construction of the contour map of the (eU-eTh/3.5) in the different rock units. The highest percent of uranium migration- out or leaching rate is connected with the red and pink granites of Gebel Kadabora El-hamra, metadiorite, and red and pink granites of G. Umm Rakham (??20.8%, ??18.57%, and ??8.45% respectively), which indicates that they could represent a major U-source bodies in the area. It was observed that the metasediments and associated graphite-bearing schists west and northwest of G. Kadabora El-hamra reflect more precipitation than the other locations around the pluton (the uranium migration rates varies between 2.59 and 30%) which mean that the graphite may have acted as a reducing agent for uranium carried in oxidizing fluids (surface meteoric water) and resulted in its precipitation. In the light of the availability of uranium source, its mobility, and graphite-bearing metasediments, the area has a good potential for the possible occurrence of uranium mineralization.  相似文献   
109.
The paper presents the results of a study into the relationship between water color on the Forel scale, the dominant wavelength in the radiation spectrum of the sea, and color purity.  相似文献   
110.
A 3000 km2 multibeam survey was carried out on the eastern Anaximander Mountains (Mts), (Eastern Mediterranean). The objective was to obtain detailed bathymetry of known mud volcanoes and identify new sites of active mud volcanism in the area. N-NW of the Amsterdam Mud-Volcano (MV) several mounds and cone-like morphological irregularities with a height of few tens of meters to about one hundred meters were detected and considered as potential MVs on the basis of their distinctive backscattered character. A group of two mounds was selected, the northern mound was sampled, documented as active, and named accordingly Athina MV. These new findings strongly support the presence of extensive active mud volcanism in the Anaximander Mountains especially in the area north of the Amsterdam MV.GEM  相似文献   
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