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111.
The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify 137Cs levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While measured 137Cs levels were found to be very low (usually <1 Bq kg−1 wet wt) 137Cs activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area.  相似文献   
112.
During the Russian Academy of Sciences “MIRI na Baikale, 2008–2010” expedition, deep-water experiments with the bubbles of methane seeping from the bottom at depths 405, 860 and 1400 meters were carried out. These depths correspond to gas hydrate stability zone. Bubbles were caught by the trap which was looked like an inverted glass. It was found that the behavior of bubbles in a trap depends on the depth. At depth of 405 meters formation of hydrates was not observed. Having got to a trap at the depth of 860 meters, bubbles became covered by solid hydrate envelope, kept the initial form, and after a time period collapsed in a number of hydrate fragments which showed all properties of a granular matter. No visible changes in the hydrate granular matter were observed in the course of lifting it to a depth of 380 meters. Shallower, the decomposition of the hydrate granular matter into methane gas was observed. In the experiments at depth of 1400 meters the caught bubbles, becoming covered by hydrate envelope formed solid hydrate foam in the trap. At lifting this foam structure was deformed slightly but simultaneously a free gas left the foam and filled the trap. The volume of free gas in the trap at lifting varied according to the Boyle-Mariotte law.  相似文献   
113.
Egorov  Yu. A. 《Water Resources》2002,29(5):567-572
Information on 3H release at nuclear power plants (NPP), its escape beyond NPP and migration in the atmosphere and cooling pool is generalized and analyzed. It is shown that 3H that has formed in the process of NPP operation and entered the environment is not a radiation hazard to the population and natural objects.  相似文献   
114.
The results of gas geochemical and seismoacoustic measurements obtained in the course of the expedition for the studies of gas seepages at the Anapa shelf of the Black Sea are presented. According to the data of the gas survey in the surface waters of the Anapa shelf, a large methane anomaly was discovered and mapped. The correlation of the anomaly with the bottom sources located over the Pionerskaya structure is proved. The geological structure of the area studied is analyzed. The data set allowed us to positively characterize the prospects of the oil-and-gas content of the Anapa shelf interiors and of the Pionerskaya structure proper.  相似文献   
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工程勘察节水钻探技术以一种新的技术思路,采用脉动器、孔内潜水泵和排气阀三个部件在原有的钻探设备与机具的基础上,实现利用孔内地层水冲洗循环钻进,不消耗地表水,并减少孔内漏失。本文着重介绍了该技术的设计思路、工作原理与室内试验、野外生产应用试验等内容,研究与试验表明,节水型钻探新技术工作原理先进,工作性能可靠,对地表缺水与孔内漏失条件下工程勘察的钻探工程提供有效的技术保障,具有广阔的研究应用前景。  相似文献   
117.
We continue our study (Grechnev et al., 2013, doi: 10.1007/s11207-013-0316-6 ; Paper I) on the 18 November 2003 geoffective event. To understand possible impact on geospace of coronal transients observed on that day, we investigated their properties from solar near-surface manifestations in extreme ultraviolet, LASCO white-light images, and dynamic radio spectra. We reconcile near-surface activity with the expansion of coronal mass ejections (CMEs) and determine their orientation relative to the earthward direction. The kinematic measurements, dynamic radio spectra, and microwave and X-ray light curves all contribute to the overall picture of the complex event and confirm an additional eruption at 08:07?–?08:20 UT close to the solar disk center presumed in Paper I. Unusual characteristics of the ejection appear to match those expected for a source of the 20 November superstorm but make its detection in LASCO images hopeless. On the other hand, none of the CMEs observed by LASCO seem to be a promising candidate for a source of the superstorm being able to produce, at most, a glancing blow on the Earth’s magnetosphere. Our analysis confirms free propagation of shock waves revealed in the event and reconciles their kinematics with “EUV waves” and dynamic radio spectra up to decameters.  相似文献   
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By analogy with other metallogenic belts of the Circum-Pacific ring, the metallogenic belts in the Northeast of Russia are promising for discovery of large and superlarge porphyry-type Au-Cu-Mo deposits. The spatial distribution of these deposits is controlled by intrusive domes in Middle Paleozoic, Late Jurassic-Early Cretaceous, and Late Cretaceous volcanic belts. New data on formation conditions and sources of ore matter are presented in this paper with respect to the deposits of the Baim and Koni-P’yagina ore districts of the Oloi and Uda-Murgal metallogenic belts. Some aspects of a geological and genetic model of the porphyry copper ore-magmatic system are discussed.  相似文献   
120.
Sevastopol Bay is used as an example for the development of criteria for rating anthropogenic impact by elimination fluxes from the water area of post-Chernobyl (90Sr, 137Cs, 239,240Pu) and natural (210Pо) radionuclides, as well as mercury and organochlorine compounds. The differentiation of the bay water area into zones with different biogeochemical conditions and the balance approach to interpreting field observation data were used to assess the conditioning capacity of Sevastopol Bay ecosystem for conservative radioactive and chemical substances by elimination fluxes of pollutants into aqueous depot, which is the open part of the Black Sea and into the geological depot, i.e., its bottom sediment stratum.  相似文献   
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