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991.
Ghislain Dubois Benjamin Sovacool Carlo Aall Maria Nilsson Carine Barbier Alina Herrmann Sébastien Bruyère Camilla Andersson Bore Skold Franck Nadaud Florian Dorner Karen Richardsen Moberg Jean Paul Ceron Helen Fischer Dorothee Amelung Marta Baltruszewicz Jeremy Fischer Françoise Benevise Valérie R. Louis Rainer Sauerborn 《Chemie der Erde / Geochemistry》2011
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy. 相似文献
992.
Consolidation and deformation around stone columns: Numerical evaluation of analytical solutions 总被引:1,自引:0,他引:1
Coupled finite element analyses of the consolidation and deformation around stone columns have been performed to assess the accuracy of different analytical solutions. The numerical model reproduces the hypotheses of the closed-form solutions. In the model, a rigid load is applied to a unit cell formed by a fully penetrating column and its surrounding soil, and simple elastic or elasto-plastic soil models are used. The surface settlement, the dissipation of the pore pressure and the vertical stress concentration on the column are studied. These soil responses are accurately estimated with closed-form solutions that properly include the radial and plastic strains in the column. However, the surrounding soil does not yield for usual conditions, which reasonably justifies the elastic soil behavior assumed in the analytical solutions. The differences between drained and consolidation analyses are also evaluated. Comparing the numerical results with the closed-form solutions illustrates the implications of the assumptions of each approach. 相似文献
993.
Evidence that Synchrotron Emission from Nonthermal Electrons Produces the Increasing Submillimeter Spectral Component in Solar Flares 总被引:1,自引:0,他引:1
Adriana V. R. Silva G. H. Share R. J. Murphy J. E. R. Costa C. G. Giménez de Castro J.-P. Raulin P. Kaufmann 《Solar physics》2007,245(2):311-326
We investigate the origin of the increasing spectra observed at submillimeter wavelengths detected in the flare on 2 November
2003 starting at 17:17 UT. This flare, classified as an X8.3 and 2B event, was simultaneously detected by RHESSI and the Solar
Submillimeter Telescope (SST) at 212 and 405 GHz. Comparison of the time profiles at various wavelengths shows that the submillimeter
emission resembles that of the high-energy X rays observed by RHESSI whereas the microwaves observed by the Owens Valley Solar
Array (OVSA) resemble that of ∼50 keV X rays. Moreover, the centroid position of the submillimeter radiation is seen to originate
within the same flaring loops of the ultraviolet and X-ray sources. Nevertheless, the submillimeter spectra are distinct from
the usual microwave spectra, appearing to be a distinct spectral component with peak frequency in the THz range. Three possibilities
to explain this increasing radio spectra are discussed: (1) gyrosynchrotron radiation from accelerated electrons, (2) bremsstrahlung
from thermal electrons, and (3) gyrosynchrotron emission from the positrons produced by pion or radioactive decay after nuclear
interactions. The latter possibility is ruled out on the grounds that to explain the submillimeter observations requires 3000
to 2×105 more positrons than what is inferred from X-ray and γ-ray observations. It is possible to model the emission as thermal; however, such sources would produce too much flux in the
ultraviolet and soft X-ray wavelengths. Nevertheless we are able to explain both spectral components at microwave and submillimeter
wavelengths by gyrosynchrotron emission from the same population of accelerated electrons that emit hard X rays and γ rays. We find that the same 5×1035 electrons inferred from RHESSI observations are responsible for the compact submillimeter source (0.5 arcsec in radius) in
a region of 4500 G low in the atmosphere, and for the traditional microwave spectral component by a more extended source (50
arcsec) in a 480 G magnetic field located higher up in the loops. The extreme values in magnetic field and source size required
to account for the submillimeter emission can be relaxed if anisotropy and transport of the electrons are taken into account. 相似文献
994.
Air temperature and wind measurements on the surface and in the free atmosphere taken during the total solar eclipse of July 11, 1991, are analyzed. Surface air temperature decreased significantly, 2 to 5 °C in general, with the lowest values occurring 10 to 30 minutes after totality. In some places, surface wind speed decreased gradually during the eclipse, as a result of the decrease of air temperature and temperature gradients. In other places, it increased due to local atmospheric conditions. A radiosonde launched at 13:26 LT (local time) appeared to have been affected by the moon's shadow at about 13 km height. At this altitude temperature was relatively lower than usual and the balloon carrying the radiosonde experienced an upward acceleration. Also at this altitude wind direction changed and wind speed decreased 相似文献
995.
Besides the traditional post-separation residential arrangement in which the children live with the mother and have regular contact with the father, new arrangements have emerged and become more widespread in which parents strive for a more equal division of tasks. We used an explanatory mixed methods research design to enhance insight into the life course characteristics of separated parents involved in shared residence arrangements. Survey data derived from the Netherlands Kinship Panel Study (NKPS) and Divorce in the Netherlands 1998 were supplemented with information from in-depth interviews with NKPS respondents. We found that shared residence parents seem to be a typical modern category of separated parents with a specific set of characteristics. The distance between the residences of the ex-partners plays a crucial role in maintaining a shared residence arrangement. Highly educated, dual-career ex-couples, and those with high incomes are also more likely to be involved in a shared residence arrangement. Shared residence arrangements were more likely when the woman had a new partner, but less likely when the man had a new partner. Our findings on gender differences are in line with the idea that involvement in non-traditional residential arrangements is a sign of increased paternal involvement, but decreased maternal involvement, compared with the traditional arrangements. 相似文献
996.
997.
Holly L. Schrank Maria I. Marshall Adrienne Hall-Phillips Renee F. Wiatt Nicole E. Jones 《Natural Hazards》2013,65(3):2353-2374
Post-disaster research is often plagued by displacement of subjects, loss of infrastructure, and the disruption of communication. Economic losses and business disruptions caused by a disaster tend to affect small businesses on a greater scale. With the majority of small businesses being operated out of a home, the inability to recover affects both economic and overall well-being of the business and the family. Specifically for small businesses, post-disaster research is important because it leads to increased preparedness and survival strategies for the sector and reduced economic vulnerabilities in owner-controlled areas. Historically, most of what is known about preparation, response, and recovery of small businesses from natural disasters is based on businesses that have recovered. However, there exists a need for understanding recovery also from the perspective of those that tried, but failed to recover. Grounded in a pragmatic approach, this study presents a methodology for tracking demised small businesses after Hurricane Katrina. Supported by empirical evidence, solutions to the problems of timing, generalizability, and access are presented, providing a systematic methodology for successfully studying small businesses after a disaster event. Rate of survival and demise data are presented, providing more useful numbers than prior estimates. Locating demised and recovered small businesses efficiently is the first step in understanding how business owners prepare, react, adjust, and strive to recover from disaster-driven events. A solution to this challenging issue of access makes the study of demised small businesses possible. 相似文献
998.
Representative interpretation criteria are examined in detail to evaluate the lateral response of drilled shaft foundations in gravels. A database of field lateral load tests is used for the analysis. The representative criteria are subdivided into absolute displacement, displacement as a function of shaft diameter, rotation limit, mathematical model, and graphical construction method. Comparison of these criteria shows that the initial elastic region ends at approximately 3–5 mm, 0.50 %B, and 0.08° rotation, which represent the serviceability limit state. The final region begins at about 25 mm, 2.5 %B, and 0.33° rotation, which represent the ultimate limit state. The graphical construction methods, QL and QS&W, are located within the transition region of the curve. Among these criteria, the displacement limits, QL, and QS&W methods demonstrate more reliable results. The typical load–displacement curves for lateral capacity in gravels are developed for engineering practical use. Further, recommendations for the use of these interpretation criteria are also given. 相似文献
999.
Jordi Pujadas Josep Maria Casas Josep Anton Muñoz Francese Sabat 《Geodinamica Acta》2013,26(3):195-206
AbstractThe structure of the southern Pyrenees, east of the Albanyà fault (Empordà area), consists of several Alpine thrust sheets. From bottom upwards three main structural units can be distinguished : the Roc de Frausa, the Biure-Bac Grillera and the Figueres units. The former involves basement and Paleogene cover rocks. This unit is deformed by E-W trending kilometric-scale folds, its north dipping floor thrust represents the sole thrust in this area. The middle unit is formed by an incomplete Mesozoic succession overlain by Garumnian and Eocene sediments. Mesozoic rocks internal structure consists of an imbricate stack. The floor thrust dips to the south and climbs up section southwards. The upper unit exibits the most complete Mesozoic sequence. Its floor thrust is subhorizontal. The lower and middle units thrust in a piggy-back sequence. The upper unit was emplaced out of sequence.Lower Eocene sedimentation in the Biure-Bac Grillera unit was controlled by emergent imbricate thrusts and synchronic extensional faults. One of these faults (La Salut fault) represents the boundary between a platform domain in the footwall and a subsident trough in the hangingwall. Southward thrust propagation produces the inversion of these faults and the development of cleavage-related folds in their hangingwalls (buttressing effect). This inversion is also recorded by syntectonic deposits, which have been grouped in four depositional sequences. The lower sequences represent the filling on the hangingwall trough and the upper sequences the spreading of clastics to the south once the extensional movement ends. 相似文献
1000.
Massimiliano Favalli Fabrizio Innocenti Maria Teresa Pareschi Giorgio Pasquarè Stefano Branca 《Geodinamica Acta》2013,26(5):279-290
AbstractA Digital Elevation Model (DEM) of Mt. Etna is presented; it has altimetric and planimetric resolution of 1 m and 5 m, respectively, and covers an area of about 120 km . This 3-D view of Mt. Etna allowed both recognition and location of the main morphostructural and volcano-tectonic features of the volcano. A slope map has been generated from the DEM; on the basis of slope distributions and surface textures, five acclivity domains have been recognized. The largest domain, south of the summit craters, reflects the occurrence of old plateau lavas, distinct from central volcanoes which built the present Etnean volcanic system. Interaction between the central volcanoes, with their summit calderas and failed slopes, produced the other recognised domains. Furthermore, newly identified relevant morphostructural lines are discussed. © Elsevier, Paris 相似文献