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51.
This paper explores the advantages of applying the concept of social-ecological resilience (SER) and the related thinking in transdisciplinary research. The theoretical reflections are exemplified by transdisciplinary research experiences using the concept of SER as a bridging concept in the field of climate-change adaptation instead of developing a new and very context-specific conceptual bridge. The findings are based on ontological reflections concerning the complex and hybrid phenomenon of climate change and the need for transdisciplinary research as well as on reflections on the performed interdisciplinary research and the exploratory transdisciplinary research approach with practitioners from the German administration. The experiences so far have shown that it was more focused on the general ideas of social-ecological resilience thinking instead of using the concept of SER as an analytical tool. We conclude that the use of a common conceptual framework in general and of social-ecological resilience thinking in particular offers tangible advantages in transdisciplinary research dealing with climate change and adaptation to the impacts of climate change. In our case, social-ecological resilience thinking helped—after translation into practical terms—to open the field for further consideration from the very beginning as well as to open the space for common creative work; to define the problem; and to choose the relevant variables to look at.  相似文献   
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53.
The anti-microbial agent triclosan (TCS), and its derivative methyl-triclosan (Me-TCS), are discharged with treated effluents from wastewater treatment plants to receiving environments. We investigated the bioconcentration of TCS and Me-TCS in mussels (Mytilus galloprovincialis) exposed to TCS (100 ng L−1) for 30 days in seawater aquaria (19 ± 2 °C) with fresh phytoplankton as a food source. Bioconcentration increased with time reaching a steady-state around 24–30 days. The bioconcentration factor (log BCF) for TCS were 2.81 L kg−1 (dry weight) and 4.13 L kg−1, when lipid normalised concentrations were used. Mussels were also deployed in cages at four marine locations receiving effluents from WWTPs. The mean (±SD) TCS and Me-TCS concentrations for mussels from these sites were 9.87 (±1.34) and 6.99 (±2.44) μg kg−1. The study showed that mussels can be a useful tool for monitoring pollution of TCS and Me-TCS in marine and estuarine environments.  相似文献   
54.
Mineralogy and Petrology -  相似文献   
55.
Despite a great deal of research on public perceptions of climate change science, very little empirical work has attempted to investigate how members of the lay public might evaluate the justice dilemmas inherent within climate policy decision-making. This exploratory study contrasts arguments about justice from a mitigation perspective, with those from an adaptation perspective and draws insights about the contours of politically acceptable climate policy. Using think-aloud protocols and a structured elicitation approach with members of the lay public to generate quantitative and qualitative data, this study suggests that the two types of climate policy trigger different sets of arguments about justice. When asked about mitigation burden-sharing participants overwhelmingly invoke arguments about causality. In contrast, in discussions of adaptation participants emphasized the needs of the afflicted parties and their ability to cope. Furthermore, social and spatial distances were not a factor in allocation of mitigation burdens, but were used to discount the distribution of compensation towards adaptation. These initial data about public perceptions of justice in this area suggest that the public would view adaptation and mitigation as complements not substitutes. These findings also highlight the importance of exploring public reactions to the sub-components of climate policy individually.  相似文献   
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In 2007, a companion with planetary mass was found around the pulsating subdwarf B star V391 Pegasi with the timing method, indicating that a previously undiscovered population of substellar companions to apparently single subdwarf B stars might exist. Following this serendipitous discovery, the EXOTIME (http://www.na.astro.it/~silvotti/exotime/) monitoring program has been set up to follow the pulsations of a number of selected rapidly pulsating subdwarf B stars on time scales of several years with two immediate observational goals:
  1. determine $\dot{P}$ of the pulsational periods P
  2. search for signatures of substellar companions in O–C residuals due to periodic light travel time variations, which would be tracking the central star’s companion-induced wobble around the centre of mass
These sets of data should therefore, at the same time, on the one hand be useful to provide extra constraints for classical asteroseismological exercises from the $\dot{P}$ (comparison with “local” evolutionary models), and on the other hand allow one to investigate the preceding evolution of a target in terms of possible “binary” evolution by extending the otherwise unsuccessful search for companions to potentially very low masses. While timing pulsations may be an observationally expensive method to search for companions, it samples a different range of orbital parameters, inaccessible through orbital photometric effects or the radial velocity method: the latter favours massive close-in companions, whereas the timing method becomes increasingly more sensitive toward wider separations. In this paper we report on the status of the on-going observations and coherence analysis for two of the currently five targets, revealing very well-behaved pulsational characteristics in HS?0444+0458, while showing HS?0702+6043 to be more complex than previously thought.  相似文献   
58.
High-spatial resolution analysis of light element isotope variations by secondary-ion mass spectrometry (SIMS) has numerous applications in geochemistry and cosmochemistry. Recent attention has focused on 7Li/6Li variations in magmatic phenocrysts to infer the volatile degassing history of their parent magmas, and on minerals from mantle samples to determine source-region processes and the recycling history of mantle reservoirs. In these studies the effect of mineral composition on the 7Li/6Li ratio measured by SIMS has been considered secondary, and generally disregarded. We show, using a suite of nine olivines analyzed by MC-ICP-MS or TIMS, that there is a substantial effect of composition on the 7Li/6Li ratio of olivine measured by SIMS. For magnesian olivine (74 < Fo < 94) the effect is a linear function of composition, with δ7Li increasing by 1.3‰ for each mole percent decrease in forsterite component. At higher Fe contents, the relationship ceases to be linear. The composition range over which linear behavior is exhibited appears to depend on instrumental conditions. A calibration of this matrix effect over the linear range is presented, assuming the measurement of 7Li/6Li relative to an olivine standard of known composition. Application of this calibration to a suite of olivines separated from basaltic lavas from Ko'olau, Hawai'i demonstrates that the matrix effect is responsible for a geologically spurious correlation between δ7Li and Mg#. However, after correction, the olivines retain evidence of Li isotope heterogeneity, the degree and nature of which differs in each of the four separates studied. These results emphasize the importance of compositional correction for SIMS measurement of δ7Li in olivine, particularly in zoned crystals, and support previous conclusions that Li isotope variability in igneous materials is subject to late-stage disturbance. The significant matrix effect demonstrated for olivine suggests that matrix effects in other minerals require further evaluation.  相似文献   
59.
Sulfide inclusions in diamonds from the 90-Ma Jagersfontein kimberlite, intruded into the southern margin of the Kaapvaal Craton, were analyzed for their Re–Os isotope systematics to constrain the ages and petrogenesis of their host diamonds. The latter have δ13C ranging between −3.5 and −9.8‰ and nitrogen aggregation states (from pure Type IaA up to 51% total N as B centers) corresponding to time/temperature history deep within the subcontinental lithospheric mantle. Most sulfides are Ni-poor ([Ni + Co]/Fe = 0.05–0.25 for 15 of 17 inclusions), have elevated Cu/[Fe + Ni + Co] ratios (0.02–0.36) and elemental Re–Os ratios between 0.5 and 46 (12 of 14 inclusions) typical of eclogitic to more pyroxenitic mantle sources. Re–Os isotope systematics indicate two generations of diamonds: (1) those on a 1.7 Ga age array with initial 187Os/188Os (187Os/188Osi) of 0.46 ± 0.07 and (2) those on a 1.1 Ga array with 187Os/188Osi of 0.30 ± 0.11. The radiogenic initial Os isotopic composition for both generations of diamond suggests that components with high time-integrated Re–Os are involved, potentially by remobilization of ancient subducted oceanic crust and hybridization of peridotite. A single sulfide with higher Os and Ni content but significantly lower 187Os/188Os hosted in a diamond with less aggregated N may represent part of a late generation of peridotitic diamonds. The paucity of peridotitic sulfide inclusions in diamonds from Jagersfontein and other kimberlites from the Kaapvaal craton contrasts with an overall high relative abundance of diamonds with peridotitic silicate inclusions. This may relate to extreme depletion and sulfur exhaustion during formation of the Kaapvaal cratonic root, with the consequence that in peridotites, sulfide-included diamonds could only form during later re-introduction of sulfur.  相似文献   
60.
Summary. Independent sets of LISPB data are presented, having as a common feature a local lateral variation in the Moho beneath northern Britain.
The evidence for this step-like feature on the Moho is taken from P and S travel times and from PS reflection times and phase velocities.
Another important observation is that a high-frequency Moho refraction is generated north of the step, whilst the refraction from the step region and south of it contains only low frequencies. This leads to the assumption that a change in the Moho structure exists in the same region as where the step has been deduced from travel-time interpretation. A numerical model is presented which generates a high-frequency refracted wave from an input signal which contains low- and high-frequency spectral energy.
The significance of this offset on the Moho, in particular its relationship to surface tectonics, is critically discussed.  相似文献   
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