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This article is an English translation of the work cited in 46: 3092. The authors review the conclusions of Pivovarov (see 44: Title 3118) concerning the nature of the urbanization process and optimal city size in the USSR. The relationship between urbanization and the characteristics of a given socioeconomic system is examined, and the possibility of determining optimal size for cities of different functional types is evaluated  相似文献   
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Elevated turbidity (Tn) and suspended sediment concentrations (SSC) during and following flood events can degrade water supply quality and aquatic ecosystem integrity. Streams draining glacially conditioned mountainous terrain, such as those in the Catskill Mountains of New York State, are particularly susceptible to high levels of Tn and SSC sourced from erosional contact with glacial-related sediment. This study forwards a novel approach to evaluate the effectiveness of stream restoration best management practices (BMPs) meant to reduce stream Tn and SSC, and demonstrates the approach within the Stony Clove sub-basin of the Catskills, a water supply source for New York City. The proposed approach is designed to isolate BMP effects from natural trends in Tn and SSC caused by trends in discharge and shifts in average Tn or SSC per unit discharge (Q) following large flood events. We develop Dynamic Linear Models (DLMs) to quantify how Tn-Q and SSC-Q relationships change over time at monitoring stations upstream and downstream of BMPs within the Stony Clove and in three other sub-basins without BMPs, providing observational evidence of BMP effectiveness. A process-based model, the River Erosion Model, is then developed to simulate natural, hydrology-driven SSC-Q dynamics in the Stony Clove sub-basin (absent of BMP effects). We use DLMs to compare the modelled and observed SSC-Q dynamics and isolate the influence of the BMPs. Results suggest that observed reductions in SSC and Tn in the Stony Clove sub-basin have been driven by a combination of declining streamflow and the installed BMPs, confirming the utility of the BMPs for the monitored hydrologic conditions.  相似文献   
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Summary Early Proterozoic layered intrusions, about 2440 Ma in age, are widespread over a large area of the northeastern Fennoscandian Shield in Finland, Sweden and the Soviet Union. Only one intrusion, the Kukkola intrusion, is encountered in Sweden whereas in Finland, their number exceeds twenty. These are concentrated principally in two areas, the dicontinuous Tornio-Närdnkävaara intrusion belt which crosses northern Finland and the Koitelainen intrusion with its satellites located in central Finnish Lapland. The intrusions in the Soviet Union are concentrated in three areas: (i) on the Kola Peninsula, (ii) in the Paanajärvi area close to the Finnish border and (iii) northeast of Lake Onega.Examples of all the ore types characteristic of layered intrusions have been found in these intrusions. Chromitite layers are encountered in the Kukkola/Tornio, Kemi, Penikat, Koitelainen and Burakovsky intrusions, but only one, the Kemi chromitite, has so far been mined. The Portimo, Koillismaa, Monchegorsk and Fedorova intrusions are characterized by PGE-bearing Cu-Ni-deposits in their marginal series. Mineralized zones enriched in PGE are also encountered in the layered series. Those in the Penikat intrusion and in the Portimo intrusions are the most remarkable and the best known to date. Vanadium-bearing Fe-Ti-oxide layers are encountered in several intrusions, but only one, the Mustavaara deposit, is presently being exploited.Two types of parental magma have tentatively been proposed for these intrusions. The first type is represented by a magma which was relatively rich in magnesium and chromium and was as a whole boninitic in composition, whereas the plagioclase-rich intrusions and megacyclic units are interpreted as having crystallized from a magma which was greatly depleted in these elements, especially Cr, and had melted crustal material incorporated in it.The emplacement of the early Proterozoic layered intrusions in Fennoscandia was part of the world-wide igneous activity indicated by other layered intrusions and mafic dyke swarms of similar age in other ancient cratons, i.e. the Jimberlana intrusion in Australia, the Great Dyke in Zimbabwe, the Scouric picrite suite in Scotland, the Hearst-Matachewan dyke swarm, Copper Cliff Formation and East Bull Lake intrusion in Ontario, Canada, and the Vestfold Hills and Napier Complex dyke swarms in Antarctica. This almost contemporaneous occurrence in different parts of the world would suggest a more intimate relationship between the Fennoscandian Shield, northwest Scotland, Canadian Shield, Yilgarn Block, Zimbabwe Craton and East Antarctic Shield at the beginning of the Proterozoic than at present.
Früh-Proterozoische geschichtete Intrusionen im nordöstlichen Teil des Fennoskandischen Schildes
Zusammenfassung Im Nordost-Teil des Fennoskandischen Schildes in Finnland, Schweden und der Sowjetunion kommen fast vierzig frühproterozoische geschichtete Intrusionen, die ungefähr 2440 Mio J. alt sind, vor. Nur eine davon, die Kukkola Intrusion, liegt in Schweden, während in Finnland mehr als zwanzig Intrusionen vorkommen. Diese sind hauptsächlich in zwei Gebieten konzentriert, nämlich in dem nicht-zusammenhängenden Tornio-Näränkävaara Gürtel, der das nördliche Finnland durchzieht, und die Koitelainen-Intrusion mit ihren Satelliten im zentralen Finnischen Lapland. Die Intrusionen in der Sowjetunion sind in drei Gebieten konzentriert: (i) auf der Kola Halbinsel (ii) im Paanajärvi Gebiet nahe der Finnischen Grenze und (iii) östlich vom Onega-See.Beispiele aller für geschichtete Intrusionen charakteristischen Erztypen kommen vor. Chromititlagen sind in den Intrusionen von Kukkola/Tornio, Kemi, Penikat, Koitelainen und Burakovsky zu finden, aber nur eine davon, der Kemi Chromitit, ist bisher in Abbau genommen worden.Die Portimo-, Koillismaa-, Monchegorsk- und Fedorova-Intrusionen werden durch PGE-führende Kupfer-Nickel-Lagerstätten in ihren randlichen Bereichen charakterisiert. Mineralisierte Zonen die an PGE angereichert sind kommen auch in den geschich teten Serien vor. Die bemerkenswertesten sind die PGE-Vererzungen der Penikat- und der Portimo-Intrusionen. Vanadium-führende Fe-Ti-Oxidlagen kommen in verschiedenen Intrusionen vor, aber nur eine davon, die Mustavaara-Lagerstätte, ist bisher abgebaut worden.Diese Intrusionen werden auf zwei verschiedene Magmentypen zurückgeführt. Ersteres ist ein Magma das relativ reich an Magnesium und Chrom war und eine boninitische Zusammensetzung hatte, während die Plagioklas-reichen Intrusionen, und die megazyklischen Einheiten auf ein Magma das an diesen Elementen (besonders Cr) verarmt war, und das Krustenmaterial aufgeschmolzen hat, zurückgehen.Die Platznahme der frühproterozoischen geschichteten Intrusionen in Fennoskandien stellt einen Teil weltweiter magmatischer Aktivität dar, die durch andere geschichtete Intrusionen und mafische Gänge von fast identischem Alter in anderen alten Kratonen repräsentiert wird. Hier ist die Jimberlana-Intrusion in Australien, der Great Dyke in Zimbabwe, die Pikrit-Suite von Scourie in Schottland, die Gänge von Hearst-Matachewan, die Copper Cliff Formation und die East Bull Lake Intrusion in Ontario, Kanada ebenso wie die Gangsysteme der Vesthold Hills und des Napier Komplexes in Antarctica zu nennen. Diese fast gleichaltrigen Vorkommen in verschiedenen Teilen der Welt weisen auf eine engere Beziehung zwischen dem Fennoskandischen Schild, Nordwest-Schottland, dem Kanadischen Schild, dem Yilgarn Block, dem Zimbabwe-Craton und dem Ostantarktischen Schild zum Beginn des Proterozoikums hin.


With 7 Figures  相似文献   
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This paper traces the theoretical development of the regional concept and the use of regionalization techniques in Soviet geography and seeks to compare this history with comparable trends in Western geography. It is severely critical of the major and rapid paradigm shifts noticed in post-war Western geographical science and relates these to shifts in the approach to global development issues.  相似文献   
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It is found that the surface bog temperature and bog water level position are major factors that determine CO2 emission from the bog massif. The emission intensity increases with increasing temperature and with a bog water level decrease. The dependence of CO2 emission is shown to be different for each bog microlandscape. Monthly mean CO2 emissions are given for the central bog massif in the years with different water content. Based on modeling, it is shown that in the case of a low bog water level the CO2 flux is directed to the atmosphere (the emission value exceeds the gas amount consumed for photosynthesis), while in the case of a high level, it is taken up by the growing plants.  相似文献   
8.
This article proposes a methodology to analyse the composition of very small carbonate samples such as larval fish otoliths. The chemical composition of otoliths, which are carbonate structures in the inner ear, is often used to explore population dynamics in fishes. Recent advances in laser ablation‐inductively coupled plasma‐mass spectrometry have suggested its potential application to this field. In this study, analyses were performed using a 193 nm ArF Resonetics LA system, coupled to an Agilent 7700X‐ICP‐MS, with the following ablation parameters: a beam diameter of 5 μm, energy of 3 mJ, 2.7 J cm?2, laser repetition rate of 10 Hz and translation speed of 2.5 μm s?1. NIST SRM 610 glass was used as the primary calibration material. Performing this protocol, characterisation of a USGS GP‐4 reference material was achieved with suitable precision and accuracy, but the USGS MACS‐3 reference material appeared more heterogeneous under the ablation conditions tested. Calibration was performed using two different beam diameters (5 and 11 μm). Capelin (Mallotus villosus) otoliths measuring between 10 and 20 μm in diameter were tested. Even though a smaller beam diameter and lower energy were used compared with those normally employed to analyse larger otoliths, the method was successful.  相似文献   
9.
Institutional capacity is an important element for climate change adaptation (CCA) and the development of such capacity is a great challenge in a Least Developed Country like Cambodia where resources are limited. An important first step to increasing capacity is via an understanding of the level of existing capacity; future priorities can then be subsequently identified. This study aimed to assess the capacity of organizations to implement climate change activities in Cambodia in order to provide such a basis for building capacity. Four elements of capacity were investigated in this research: (1) financial resources, (2) cooperation and coordination of stakeholders, (3) availability and quality of information on vulnerability and adaptation to climate change, and (4) the level of understanding of climate change vulnerability and adaptation. The data were collected through semistructured interviews with a wide range of government and non-government informants across a number of sectors. Results of the study showed that informants perceived capacity for CCA to be very constrained, especially in terms of financial resources and cooperation, and addressing these factors was ranked as the highest climate change capacity priority. Institutional capacity constraints were considered to relate more generally to weak governance of CCA. In light of our research findings, the absence of local higher education institutions in CCA activities should be addressed. The support of such institutions would provide an important mechanism to progress both capacity development as well as partnerships and coordination between different types of organizations and relevant sectors.

Policy relevance

Capacity for CCA within Cambodian health and water sectors was perceived to be very constrained across a range of interdependent factors. Increasing funding was ranked as the highest priority for building capacity for CCA; however, governance factors such as ‘improved cooperation’ were also ranked highly. Improving stakeholders' awareness of the availability of adaptation funds and resources, and their responsiveness to funding criteria, is an important implication of our research, as is improving the mobilization of local resources and the private sector. To address the issue of weak cooperation among stakeholders, improving the coordination function of the National Climate Change Committee (NCCC) regarding stakeholder engagement and capacity building is crucial. Ensuring that CCA activities are based on sound information and knowledge from across different disciplines and, importantly, include the perspectives of vulnerable people themselves, ultimately underpins and supports the realization of the above priorities.  相似文献   
10.
Using a spherically symmetric approximation for the radiation pressure force to compute a possible critical surface for binary systems, previous authors found that the surface opens up at the far side of the companion. It is shown that this effect may be unreal, and could be a consequence of the simple approximation for the radiation pressure force. Due to the influence of the radiation force, mass will be lost over the whole surface of the star. In that way much mass could leave the system in massive binary systems. On the basis of evolutionary models, including mass loss by stellar wind, our results were applied on the X-ray binaries 3U 1700-37 and HD 77581.  相似文献   
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