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21.
Political regulation has traditionally been regarded as antagonistic to innovation, whereas the removal of regulations has been perceived as a precondition for innovations. This paper proposes an alternative position and claim that regulations can have various connections with the innovation process. Regulations can obviously restrict innovations, but they can also facilitate such processes. Systematic empirical research on the relation between political-administrative regulation and innovation has been moderate, and the debate has been highly anecdotal. This article presents an empirical study on how political-administrative regulation within the pelagic fisheries sector in Norway affects innovation. The study confirms that regulations had varied influences on the innovation process, and documents that actor's appraisals of regulations were affected by whether a given regulation is beneficial for the firms and their competitive position or not. Finally, the paper corroborate that the implementation of regulations can promote innovation in firms by providing them with deeper insights into their production processes and to encourage a more intense focus on development and improvement. Implementation of regulations also implies learning, which can increase the firms’ abilities to innovate as well as their insight into the necessity of such practices. The analysis is based on survey data from processors and vessels in the pelagic sector. 相似文献
22.
Hanne H. Christiansen Ole Bennike Jens Bcher Bo Elberling Ole Humlum Bjarne H. Jakobsen 《第四纪科学杂志》2002,17(2):145-160
Terraces of different age in the Zackenberg delta, located at 74°N in northeast Greenland, have provided the opportunity for an interdisciplinary approach to the investigation of Holocene glacial, periglacial, pedological, biological and archaeological conditions that existed during and after delta deposition. The raised Zackenberg delta accumulated mainly during the Holocene Climatic Optimum, starting slightly prior to 9500 cal. yr BP (30 m a.s.l.) and continued until at least 6300 cal. yr BP (0.5 m a.s.l.). Evidence of sea‐level change is based on conventional 14C dates of shells from the marine delta bottomsets, 14C AMS dating of macroscopic plant material from the foresets and of fluvial deposits. Arthropod and plant remains from 7960 cal. yr BP in the delta foresets include the oldest evidence of the arctic hare in Greenland and evidence of a rich herb flora slightly different from the modern flora. Empetrum nigrum and Salix herbacea remains indicate a summer temperature at least as high as today during delta deposition. Post‐depositional nivation activity, dated by luminescence, lichenometry and Schmidt Hammer measurements indicate mainly late Holocene activity, at least since 2900 yr BP, including Little Ice Age (LIA) avalanche activity. Pedological analyses of fossil podsols in the Zackenberg delta, including 14C AMS dating of selected organic rich B‐horizons, show continued podsol development during the Holocene Climatic Optimum and into the subsequent colder period of the late Holocene, until 3000–2400 yr BP. A Neo‐Eskimo house ruin found on the lower part of the delta, presently being eroded by the sea, is dated to AD 1800. It presumably was abandoned prior to AD 1869, and suggests that some of the last Eskimos that lived in northeast Greenland might have occupied the Zackenberg delta. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
23.
细粒酒精模型冰的弯曲强度试验研究 总被引:3,自引:0,他引:3
基于不同制冰条件和工的细粒酒精模型冰层原位悬臂弯曲强度试验,给出细料酒精模型冰弯曲强度;分析了考虑和不考虑不浮力效应对弯曲强度的差异;利用向睡向下弯曲强度结果给出该模型冰各向同性的证据;得到该冰弯曲强度与其密度、冰内未冻液含量和制冷过程可控制因子的关系,并作为定量控制模型冰质量的基础。 相似文献
24.
Svend Duggen Maxim Portnyagin Joel Baker Kaj Hoernle Nathalie Grassineau 《Geochimica et cosmochimica acta》2007,71(2):452-480
The shift of lava geochemistry between volcanic front to rear-arc volcanoes in active subduction zones is a widespread phenomenon. It is somehow linked to an increase of the slab surface depth of the subducting oceanic lithosphere and increasing thickness of the mantle wedge and new constraints for its causes may improve our understanding of magma generation and element recycling in subduction zones in general. As a case study, this paper focuses on the geochemical composition of lavas from two adjacent volcanic centres from the volcanic front (VF) to rear-arc (RA) transition of the Southern Kamchatkan subduction zone, with the aim to examine whether the shift in lava geochemistry is associated with processes in the mantle wedge or in the subducted oceanic lithosphere or both. The trace element and O-Sr-Nd-Hf-Pb (double-spike)-isotopic composition of the mafic Mutnovsky (VF) and Gorely (RA) lavas in conjunction with geochemical modelling provides constraints for the degree of partial melting in the mantle wedge and the nature of their slab components. Degrees of partial melting are inferred to be significantly higher beneath Mutnovsky (∼18%) than Gorely (∼10%). The Mutnovsky (VF) slab component is dominated by hydrous fluids, derived from subducted sediments and altered oceanic crust, eventually containing minor but variable amounts of sediment melts. The composition of the Gorely slab component strongly points to a hydrous silicate melt, most likely mainly stemming from subducted sediments, although additional fluid-contribution from the underlying altered oceanic crust (AOC) is likely. Moreover, the Hf-Nd-isotope data combined with geochemical modelling suggest progressive break-down of accessory zircon in the melting metasediments. Therefore, the drastic VF to RA shift in basalt chemistry mainly arises from the transition of the nature of the slab component (from hydrous fluid to melt) in conjunction with decreasing degrees of partial melting within ∼15 km across-arc. Finally, systematic variations of key inter-element with high-precision Pb-isotope ratios provide geochemical evidence for a pollution of the Mutnovsky mantle source with Gorely melt components but not vice versa, most likely resulting from trench-ward mantle wedge corner flow. We also present a geodynamic model integrating the location of the Mutnovsky and Gorely volcanic centres and their lava geochemistry with the recently proposed thermal structure of the southern Kamchatkan arc and constraints about phase equilibria in subducted sediments and AOC. Herein, the slab surface hosting the subducted sediments suffers a transition from dehydration to melting above a continuously dehydrating layer of AOC. Wider implications of this study are that an onset of (flush-) sediment melting may ultimately be the main trigger for the VF to RA transition of lava geochemistry in subduction zones. 相似文献
25.
Jarle Aarstad Stig-Erik Jakobsen 《Norsk geografisk tidsskrift. Norwegian journal of geography》2019,73(5):290-300
ABSTRACTThe purpose of the article is to assess whether an entrepreneurial causation or effectuation logic is a function of geographical location in densely populated economic regions versus sparsely populated economic regions. A causation logic implies that the entrepreneur primarily focuses on a predefined goal and further aims to identify the means to reach that goal. By contrast, an effectuation logic implies that the entrepreneur to a larger extent focuses on the means at hand, which she or he aims at materialising into one or more goals that are not necessarily predefined. The empirical data for the study are based on an investigation and evaluation of Norwegian entrepreneurs in business incubation that are located in many different economic regions of the country. Multilevel regression analyses showed that geographical location in sparsely populated economic regions is associated with a causation logic, whereas a location in densely populated economic regions is associated with an effectuation logic. An implication of the article is that entrepreneurial stakeholders, such as policymakers, incubator managers, public and private partners, and entrepreneurs themselves should be aware of differences in causation and effectuation logics between entrepreneurs located in densely versus sparsely populated economic regions. 相似文献
26.
T-matrix approach to shale acoustics 总被引:2,自引:0,他引:2
Morten Jakobsen John A. Hudson Tor Arne Johansen 《Geophysical Journal International》2003,154(2):533-558
27.
Niels Nielsen Viggo Hansen Kaj Hansen Kr. M. Jensen Sten Folving Sofus Christiansen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):101-118
Meyer, Marlene: Settlement Patterns and Land-use in Northern Ghana—A Study of the Changes during the period 1963–1991 based on Historical Surveys and recent SPOT-images. Geografisk Tidsskrift 92:101–104. Copenhagen 1992. A study by Hunter (1966) describes how large areas along the Red Volta River bank, have been abandoned due to river blindness. The mapping of current land-use status and settlements patterns, using multispectral SPOT-satellite images, shows how the border of settlements continue to retreat, whereas new land is being reclaimed for bush fields in the abandoned areas. 相似文献
28.
Viggo Hansen Niels Nielsen Ruth Helkiær Jensen Kaf Hansen Kaj Hansen Johannes Krüger 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):91-100
Christensen, Leif: Faststående og omlejrede Saale-morånelersaflejringer. Et eksempel fra Szdding-området, Vestjylland. Geografisk Tidsskrift 82: 91–94. Copenhagen, Dec. 1, 1982. In situ clayey till materials on the Skovbjerg Bakkea, western Jutland can be recognized by crop-marks revealing pseudomorphs of ice-wedge polygons in orthogonal, random orthogonal and hexagonal patterns. The tills inside these polygonal patterns have high shear-strength values as measured by vane tests. Remoulded fossil solifluction deposits of till origin reveal stripes and deformed polygonal patterns in the crops. High strength as measured by vane are encountered below fossil solifluction deposits 4 meters below ground. 相似文献
29.
30.
Jörg Geldmacher Kaj Hoernle Barry B. Hanan Janne Blichert-Toft F. Hauff James B. Gill Hans-Ulrich Schmincke 《Contributions to Mineralogy and Petrology》2011,162(1):21-36
The broad belt of intraplate volcanism in the East Atlantic between 25° and 37° N is proposed to have formed by two adjacent
hotspot tracks (the Madeira and Canary tracks) that possess systematically different isotopic signatures reflecting different
mantle source compositions. To test this model, Hf isotope ratios from volcanic rocks from all individual islands and all
major seamounts are presented in this study. In comparison with published Nd isotope variations (6 εNd units), 176Hf/177Hf ratios span a much larger range (14 εHf units). Samples from the proposed Madeira hotspot track have the most radiogenic
Hf isotopic compositions (176Hf/177Hfm up to 0.283335), extending across the entire field for central Atlantic MORB. They form a relatively narrow, elongated trend
on the Nd vs. Hf isotope diagram (stretching over > 10 εHf units) between a depleted N-MORB-like endmember and a moderately
enriched composition located on, or slightly below, the Nd–Hf mantle array, which overlaps the proposed “C” mantle component
of Hanan and Graham (1996). In contrast, all samples from the Canary hotspot track plot below the mantle array (176Hf/177Hfm = 0.282943–0.283067) and form a much denser cluster with less compositional variation (~4 εHf units). The cluster falls between
(1) a low Hf isotope HIMU-like endmember, (2) a more depleted composition, and (3) the moderately enriched end of the Madeira
trend. The new Hf isotope data confirm the general geochemical distinction of the Canary and Madeira domains in the East Atlantic.
Both domains, however, seem to share a common, moderately enriched endmember that has “C”-like isotope compositions and is
believed to represent subducted, <1-Ga-old oceanic lithosphere (oceanic crust and possibly minor sediment addition). The lower
176Hf/177Hf ratio of the enriched, HIMU-like Canary domain endmember indicates the contribution of oceanic lithosphere with somewhat
older recycling ages of ≥1 Ga. 相似文献