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11.
Field studies in the framework of the EU funded BEEP project (Biological Effects of Environmental Pollution in Marine Coastal Ecosystems, 2001-2004) aimed at validating and intercalibrating a battery of biomarkers of contaminant exposure and effects in selected indicator species in the Mediterranean, the North Atlantic and the Baltic Seas. Major strategic goals of the BEEP project were the development of a sensitive and cost-efficient biological effects monitoring approach, delivery of information and advice to end-user groups, and the implementation of a network of biomarker researchers around Europe. Based on the main results obtained in the Baltic Sea component of the BEEP the present paper summarises and assesses the applicability of biomarkers for different regions and species in this sea area. Moreover, a general strategy and some practical considerations for the monitoring of biological effects in the Baltic Sea are outlined.  相似文献   
12.
Results are presented of a study on liver histopathology in Baltic flounder (Platichthys flesus) carried out in 2001 and 2002 in four coastal sampling areas of the Baltic Sea: Kv?d?fj?rden (Swedish east coast, reference area), Klaipeda-Butinge (Lithuanian coast), Gulf of Gdansk (Polish coast), and Wismar Bay (German coast) within the framework of the EU-funded BEEP project. Liver lesions were diagnosed and categorised using standardised methodologies and, for a spatial and temporal assessment of the prevalence and types of lesions detected, a scoring system was applied, involving the calculation of mean histopathology lesion scores. 83.0% of the 436 female flounder examined (size range: 20-43 cm total length, age range: 2-8 years) were affected by liver lesions, out of which 74.3% were assigned to the category of non-specific, 3.4% to the category of early toxicopathic non-neoplastic, 4.6% to the category of pre-neoplastic and 0.7% to the category of neoplastic lesions. Mean lesions scores were highest in the areas at the Lithuanian and Swedish coast and there is indication of an impact of the age structure of the flounder populations studied, the sampling season as well as of contaminant effects.  相似文献   
13.
Frequency of micronuclei (MN) and other nuclear abnormalities (nuclear buds, bi-nucleated and fragmented-apoptotic cells) was analysed in gill cells of the blue mussel (Mytilus spp.) from selected coastal sites in the Baltic Sea--Kv?d?fj?rden (Sweden), Klaipeda-Būtinge zone (Lithuania), Gulf of Gdansk (Poland) and Wismar Bay (Germany). Samples were collected from 650 specimens during bi-annual sampling campaigns in 2001 and 2002. The lowest frequency of MN (0.37 MN/1000 cells) was found in blue mussels from the reference site (Kv?d?fj?rden). The highest MN values (up to 6.7 MN/1000 cells) were registered in blue mussels from the Gulf of Gdansk in autumn 2001 and 2002, and at Wismar Bay in spring 2001 (up to 5.06 MN/1000 cells). Gradients of MN incidences were observed when comparing the three studied locations in Wismar Bay, and at the Lithuanian coast before the crude oil spill in the Būtinge oil terminal. Moreover, significant seasonal and inter-location differences in the responses were documented (P<0.0001). Nuclear abnormalities were observed most frequently in blue mussels from the Gulf of Gdansk.  相似文献   
14.
Measurements were made of sulphur and oxygen isotope ratios of sulphate in some Slovenian rivers, lakes and tap waters. δ34S ranged from −0.2 to + 13.3‰, δ18O ranged from +4.9 to + 13.6‰, and the sulphate content varied from 0.8 to 41.4 mg/L. Rivers flowing from the Julian Alps contain a very low amount of sulphate that is leached from a thin horizon of soil by rain. As confirmed by their low δ18O values, these sulphates do not enter the rivers directly in rain, but arise from biochemical cycling in the soil. The low δ34S of this sulphate indicates that it originates from the oxidation of sedimentary sulphides. The evolution of sulphates along the river course was investigated for the Sava and Ljubljanica rivers. The variations observed in sulphate from the waters studied result from variations in the contribution of sulphates of different origin. Downstream the Sava River sulphate is depleted in the heavy isotopes of both sulphur and oxygen, with δ-values gradually tending toward the δ-values of groundwater sulphates in the watershed. In contrast, the δ-values of sulphate in the Ljubljanica River are almost constant and similar to those of sulphate in local groundwater. Introduction of water from Italian and Slovenian mines was recorded in the Soča River, where the lowest δ34S value of sulphate sulphur (−0.2‰) was observed. In addition, the influence of sulphate from the oxidation of sedimentary sulphides was recorded in the Sotla River. No evidence was found for introduction of sulphate from factories.  相似文献   
15.
In Quaternary studies, tephras are widely used as marker horizons to correlate geological deposits. Therefore, accurate and precise dating is crucial. Among radiometric dating techniques, luminescence dating has the potential to date tephra directly using glass shards, volcanic minerals that formed during the eruption or mineral fragments that originate from the shattered country rock. Moreover, sediments that frame the tephra can be dated to attain an indirect age bracket. A review of numerous luminescence dating studies highlights the method's potential and challenges. While reliable direct dating of volcanic quartz and feldspar as a component in tephra is still methodically difficult mainly due to thermal and athermal signal instability, red thermoluminescence of volcanic quartz and the far-red emission of volcanic feldspar have been used successfully. Furthermore, the dating of xenolithic quartz within tephra shows great potential. Numerous studies date tephra successfully indirectly. Dating surrounding sediments is generally straightforward as long as samples are not taken too close to the tephra horizons. Here, issues arise from the occurrence of glass shards within the sediments or unreliable determination of dose rates. This includes relocation of radioelements, mixing of tephra into the sediment and disregarding different dose rates of adjacent material.  相似文献   
16.
The Lomza orthoamphibolites in the crystalline basement of NE Poland, dated at 1802 ± 9 Ma by SHRIMP zircon U–Pb, are characterized by high incompatible and REE element contents. These features, the low Nb, and the position of the rock compositions on La–Y–Nb, Zr–Nb/Zr and Zr–Nb–Y tectonomagmatic discrimination diagrams, suggest that the metavolcanics formed in a subduction setting, possibly within a continental margin island arc. The likely extension of the belt of Paleoproterozoic mafic magmatism from Latvia and Lithuania into NE Poland provides convincing evidence for the existence of an active plate margin in that region at that time.  相似文献   
17.
The aquifer system in the Thon Buri sedimentary basin below the deltaic flood plain of the Chao Phraya River, central Thailand, has been exploited for public water supply for the capital Bangkok since the early 1920s. Groundwater withdrawal, currently 1.4 million m3/d, has resulted in a maximum decline in hydraulic head of up to 40 m. This has induced land subsidence of as much as 1.7 m (1940–1992) in the eastern suburbs of the metropolis. Artificial injection of purified water within an area-wide network of recharge wells could constitute a remedy to slow the water level depression within the sedimentary basin, and thus the subsidence. This requires a prior shutdown of water withdrawal. The flow paths of the injected water can be traced by changes in the 87Sr/86Sr ratio of the groundwater and injected water mixture within the three main aquifers in the basin that are used for public supply. The ratios, monitored at five monitoring stations within the cone of depression, have been constant over 3 years. Injection of the calculated cone volume of 5.2?×?109 m3 would take at least 10 years, depending on the injection pressure and the number and position of wells.  相似文献   
18.
The coefficients of correlation between spectroscopic data published by Yamashita (1967) and others for carbon stars and the statistical population indices calculated for these stars at the Toru Observatory are calculated (Table II). The intensity estimates of Cai 4227 Å, Nai D lines, the C13/C12 ratio, then=n(Li/Ca) index, as well as CN and probably C2 bands are higher in population I carbon stars. The CH(G) band and probably hydrogen (H, H, H) lines as well as Baii 4554 and 4934 Å lines are stronger in population II carbon stars. The photoelectric colour indices, corrected for interstellar reddening do not show significant population effects. They can be used as spectral type equivalents. For a population criterion the CH/CN intensity ratio is proposed.  相似文献   
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