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91.
We report results from multiwavelength observations of the microquasarGRS 1915+105 performed during the 2000 April campaign. This is one ofthe biggest campaigns ever made for this source covering the broadband from radio to γ-rays. Multiwavelength light curves compiledfrom all the data reduced up to date and broad band spectra obtainedwith ASCA and RXTE are presented.  相似文献   
92.
93.
Estimation of groundwater residence time using the 36Cl bomb pulse   总被引:1,自引:0,他引:1  
We propose a methodology for estimating the residence time of groundwater based on bomb-produced (36)Cl. Water samples were collected from 28 springs and 2 flowing wells located around Mt. Fuji, Central Japan. (36)Cl/Cl ratios in the water samples, determined by accelerator mass spectrometry (AMS), were between 43 × 10(-15) and 412 × 10(-15). A reference time series of the above-background (i.e., bomb-derived) (36)Cl concentration was constructed by linearly scaling the background-corrected Dye-3 data according to the estimated total bomb-produced (36)Cl fallout in the Mt. Fuji area. Assuming piston flow transport, estimates of residence time were obtained by comparing the measured bomb-derived (36)Cl concentrations in spring water with the reference curve. The distribution of (36)Cl-based residence times is basically consistent with that of tritium-based estimates calculated from data presented in previous studies, although the estimated residence times differ between the two tracers. This discrepancy may reflect chlorine recycling via vegetation or the relatively small change in fallout rate, approximately since 1975, which would give rise to large uncertainties in (36)Cl-based estimates of recharge for the period, approximately since 1975. Given the estimated ages for groundwater from flowing wells, dating based on a (36)Cl bomb pulse may be more reliable and sensitive for groundwater recharged before 1975, back as far as the mid-1950s.  相似文献   
94.
95.
Located off the Pacific coast of central Tohoku (NE Japan), the Ishinomaki slope channel (ISC) provides an excellent opportunity to study a structure-controlled intraslope channel and downslope sedimentation along the active margin. The seismic reflection data across ISC show an extensive basal surface and overlying channel complexes between the basement structures of the Abukuma ridge to the south and Kitakami massif to the north, indicating that the formation of the intraslope basin, channelization of ISC and sedimentation of the downstream channel-lobe transition zone (CLTZ) are very likely to be structure-controlled. The oblique channel stacking pattern, faulting of the seafloor and subsurface Abukuma ridge in the upper and lower domains of ISC, collectively suggest that ISC has migrated northward and is currently under the influence of active compression. Differences in styles of accommodation space between the upper and lower domains of ISC suggest that differential subsidence occurred along the strike-slip tectonic line. Based on the regional strike-slip tectonic line, we propose that a Kitakami-Abukuma ridge existed before the formation of ISC. The strike-slip faulting divided the Kitakami-Abukuma ridge into the Kitakami massif to the north and the Abukuma ridge to the south, and an intervening fault trough as the precursor of the intraslope basin and ISC. As the subduction of the Pacific Plate and associated compressional events continued, the Abukuma ridge was reactivated to narrow the intraslope basin into a confined channel. Located near the epicentre of the devastating 2011 Tohoku earthquake event, the ISC, downstream CLTZ and underlying intraslope basin provide information on active basement structure and the evolving sediment routing system on the tectonically active margin.  相似文献   
96.
The diversity of protistan microplankton in Sagami Bay was revealed by 18S rRNA gene clone analysis using newly designed PCR primers. PCR amplification consisted of a first reaction targeting the V3–V5 region of the 18S rRNA gene, followed by a nested reaction targeting the V3–V4 region. In total, 629 clones consisting of 108 phylotypes were affiliated with a variety of protistan groups including dinoflagellates, diatoms, prymnesiomonada, chlorophyta, ciliophora, cercozoa, and heterokonta. The dinoflagellate group was detected most frequently and shared approximately 74?% of the total clones. Within this group, approximately half of the clones belonged to the parasitic dinoflagellate Syndiniales group I, which was first reported from Sagami Bay. The genera Woloszynskia, Gonyaulax, Neoceratium, and Karlodinium have not been reported from this bay until now. The second most frequent group was diatoms, which shared approximately 22?% of the total clones. Within this group, highly diverse Thalassiosira phylotypes were detected, and they shared approximately 70?% of the diatom clones. Therefore, highly diverse protists including some candidate groups were successfully detected, indicating that the designed primers and PCR protocol will be useful for molecular diversity analyses of protistan microplankton communities in aquatic environments.  相似文献   
97.
We have made a Monte Carlo simulation of the intergalactic absorption in order to model the Lyman continuum absorption, which is required to estimate the escape fraction of the Lyman continuum from distant galaxies. To input into the simulation, we derive an empirical distribution function of the intergalactic absorbers which reproduces recent observational statistics of the Lyman α forest, Lyman limit systems (LLSs) and damped Lyman α systems (DLAs) simultaneously. In particular, we assume a common functional form of the number evolution along the redshift for all types of absorbers. The Lyman series transmissions in our simulation reproduce the observed redshift evolution of the transmissions excellently, and the Lyman continuum transmission also agrees with an observed estimation which is still quite rare in the literature. The probability distribution of the Lyman α opacity in our simulation is lognormal with a tail towards a large opacity. This tail is produced by DLAs. The probability distribution of the Lyman continuum opacity in our simulation also shows a broad tail towards a large opacity. This tail is produced by LLSs. Because of the rarity of LLSs, we have a chance to have a clean line of sight in the Lyman continuum even for   z ∼ 4  with a probability of about 20 per cent. Our simulation expects a good correlation between the Lyman continuum opacity and the Lyman α opacity, which may be useful to estimate the former from the latter for an individual line of sight.  相似文献   
98.
Uptake and biological effects of synthetic glucocorticoids (GCs) were analyzed using common carp (Cyprinus carpio). Fish were exposed to clobetasol propionate (CP) or clobetasone butyrate (CB) individually or in mixture at 1 μg L−1 for 21 days. Bioconcentration factor (BCF) of CB was calculated as 100, and BCF of CP was less than 16. No effects were found in fish erythrocyte and leukocyte numbers and serum glucose levels after exposure to the selected GCs. On the other hand, serum concentrations of free amino acids significantly increased in GC-exposed groups. Thus, exposures to synthetic GCs at relatively low concentrations seemed to cause enhancement of protein degradation and subsequent increase of serum free amino acids without a corresponding increase in serum glucose levels, an effect which might be related to partial induction of gluconeogenesis by GC.  相似文献   
99.
The dynamical friction problem is a long-standing dilemma about globular clusters (hereafter GCs) belonging to dwarf galaxies. GCs are strongly affected by dynamical friction in dwarf galaxies, and are presumed to fall into the galactic centre. But, GCs do exist in dwarf galaxies generally. A solution of the problem has been proposed. If dwarf galaxies have a core dark matter halo which has constant density distribution in its centre, the effect of dynamical friction will be weakened considerably, and GCs should be able to survive beyond the age of the Universe. Then, the solution argued that, in a cored dark halo, interaction between the halo and the GC constructs a new equilibrium state, in which a part of the halo rotates along with the GC (corotating state). The equilibrium state can suppress the dynamical friction in the core region. In this study, I tested whether the solution is reasonable and reconsidered why a constant density, core halo suppresses dynamical friction, by means of N -body simulations. As a result, I conclude that the true mechanism of suppressed dynamical friction is not the corotating state, although a core halo can actually suppress dynamical friction on GCs significantly.  相似文献   
100.
Although for decades, public participation in disaster risk management has been strongly advocated for, in reality, it remains elusive. Planners and practitioners are still struggling to find ways to meaningfully involve the local community in disaster management programs; so far, apparently successful projects and initiatives have seldom been scaled up or replicated. The reason for this is that no comprehensive framework for participatory disaster risk management exists, and no systematic evaluation has been made to assess the necessary elements and appropriate paths for meaningful public participation in disaster management. This study attempts to examine the process and identify outcome-based factors that account for successful participatory disaster risk management. To accomplish this, we have evaluated reconstruction projects in earthquake-affected rural Gujarat, India, where the government envisioned a people-centric reconstruction project, but provided no public participation framework or guidelines. As a result, several reconstruction models pursuing different levels and types of public participation ultimately emerged. We selected three dominant reconstruction approaches and examined the extent to which various processes and outcome-based factors were successful in promoting ideal levels of public participation during these reconstruction projects. This study is considered an example of pioneering research in defining factors that account for successful participatory disaster risk management.  相似文献   
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