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991.
Thermal evolution and shale gas potential estimation of the Wealden and Posidonia Shale in NW‐Germany and the Netherlands: a 3D basin modelling study 下载免费PDF全文
Sedimentary basins in NW‐Germany and the Netherlands represent potential targets for shale gas exploration in Europe due to the presence of Cretaceous (Wealden) and Jurassic (Posidonia) marlstones/shales as well as various Carboniferous black shales. In order to assess the regional shale gas prospectivity of this area, a 3D high‐resolution petroleum system model has been compiled and used to reconstruct the source‐rock maturation based on calibrated burial and thermal histories. Different basal heat flow scenarios and accordingly, different high‐resolution scenarios of erosional amount distribution were constructed, incorporating all major uplift events that affected the study area. The model delivers an independent 3D reappraisal of the tectonic and thermal history that controlled the differential geodynamic evolution and provides a high‐resolution image of the maturity distribution and evolution throughout the study area and the different basins. Pressure, temperature and TOC‐dependent gas storage capacity and gas contents of the Posidonia Shale and Wealden were calculated based on experimentally derived Langmuir sorption parameters and newly compiled source‐rock thickness maps indicating shale gas potential of the Lower Saxony Basin, southern Gifhorn Trough and West Netherlands Basin. 相似文献
992.
Does carbon finance make a sustainable difference? Hydropower expansion and livelihood trade‐offs in the Red River valley,Yunnan Province,China 下载免费PDF全文
Jean‐François Rousseau 《Singapore journal of tropical geography》2017,38(1):90-107
The Kyoto Protocol's Clean Development Mechanism (CDM) is a carbon credit trading scheme intended to reduce anthropogenic greenhouse gas emissions and promote ‘sustainable development’. Hundreds of CDM‐sponsored hydroelectric dams have been constructed in southwest China's Yunnan Province, where carbon finance contributes substantial financial incentives to hydropower expansion. This article investigates whether riparian Handai farmers settled near the Madushan hydropower plant on the Chinese section of Red River have experienced positive outcomes from this project's participation in the CDM. I assess how Handai individuals' access to core livelihood assets has been modified following dam completion and probe how the CDM reconfigures scalar relations among the various stakeholders involved in hydropower governance in Yunnan. Though the CDM facilitates hydropower expansion, it fails to produce development that is more sustainable than ‘business as usual’ from a local perspective. Rather, the CDM consolidates hydropower governance in the same way as it unfolded in Yunnan before the province became an active participant in this scheme. The CDM also facilitates a national development campaign fostering specific socio‐economic modernization patterns in China's western provinces. 相似文献
993.
It's not all about wealth and beauty: Changing perceptions of fatness among Makola market women of Accra,Ghana 下载免费PDF全文
Charlotte Wrigley‐Asante Samuel Agyei‐Mensah Faustina Adomaa Obeng 《Singapore journal of tropical geography》2017,38(3):414-428
Within the African context, body shape preferences may be influenced by culture without necessarily taking into consideration health implications. Thus, fatness is culturally associated with beauty, prosperity, and prestige while thinness is perceived as a sign of ill‐health or poverty. Using a cross section of Makola market women, who traditionally are perceived as fat and affluent, our findings revealed that the perception of fatness as a sign of richness and beauty is changing due to women's access to knowledge and information on the health implications of fatness. The challenge for these women however, is adhering to healthy lifestyles despite living sedentary lives in the market place which is a conducive environment for one to become fat. We recommend that qualified professionals should encourage these women through continuous programmes on regenerative health and nutrition aimed at healthy lifestyle behaviour at the market places. The social groups that women belong to should be targeted, trained and equipped with the right information on healthy living so that they can disseminate this information to other members of their networks. 相似文献
994.
The variation of solar proton energy spectra and size distribution with heliolongitude 总被引:2,自引:0,他引:2
A statistical study of the initial phases of 185 solar particle events has been carried out using the data from the Goddard cosmic ray experiments on IMPs IV and V. Special emphasis is placed on the identification of the associated solar flare. The parent flare can be determined for 68 % of the events. It appears probable that most of the unidentified increases occur on the non-visible disc of the Sun. The existence of a preferred-connection longitude between 20°W and 80° W is established by examining the heliolongitude of all the flare associated events. While power law in differential kinetic energy appears to give the best representation it cannot be distinguished from exponential in rigidity over the limited range of 20–80 MeV. It is argued that for heliolongitudes
= 20–80°W,
p
,the spectral index determined at the time of maximum particle intensity is representative of the source spectra. For these heliolongitudes
p
displays a surprisingly small range with magnitudes varying mainly between 2.0 and 3.1. At lower energies
p
is smaller. Previous electron measurements provide almost identical average values of the source spectra over similar energy ranges. These results are discussed briefly in terms of Fermi acceleration models.For flare events located further away from the nominal field line connecting the Earth and the Sun,
p
becomes progressively steeper. The lower energies (4–20 MeV) do not exhibit this behavior. It is argued that this spectral steepening at the higher energies is the result of energy-dependent escape during the coronal diffusion process. The size distribution can be represented by a power law of the form dN/dI=I
- where N is the number of events per unit intensity and I is the maximum particle intensity at a given energy (usually taken at 40 MeV) with 1.15 ±0.1. The same value of a applies to both eastern and western hemisphere events. The event size, on the average, appears to decrease approximately two orders of magnitude for each 60° away from the preferred connection region.Also: Dept. of Physics and Astronomy, University of Maryland, College Park, Md., U.S.A. 相似文献
995.
Kim IC Chang SY Williams TD Ja Kim Y Yoon YD Lee YS Park EH Lee JS 《Marine environmental research》2004,58(2-5):687-691
We cloned the vitellogenin gene from the self-fertilizing fish Rivulus marmoratus, and sequenced 12,326 bp. The number of exons of R. marmoratus and rainbow trout vitellogenin genes were different, and also the splicing junctions are different throughout most of the exons and introns but the amino acid similarity of R. marmoratus vitellogenin gene to other species was rather high. In promoter region of R. marmoratus vitellogenin gene, there were several E2 binding sites and the estrogen response element (ERE). We discuss here the gene structure and expression of R. marmoratus vitellogenin gene. 相似文献
996.
This paper presents a technique to generate waves at oblique angles in finite difference numerical models in a rectangular grid system by using internal generation technique [Lee, C., Suh, K.D., 1998. Internal generation of waves for time-dependent mild-slope equations. Coast. Eng. 34, 35–57.] along an arc-shaped line source. Tests were made for four different types of wave generation layouts. Quantitative experiments were conducted under the following conditions: the propagation of waves on a flat bottom, the refraction and shoaling of waves on a planar slope, and the diffraction of waves to a semi-infinite breakwater. Numerical experiments were conducted using the extended mild-slope equations of Suh et al. [Suh, K.D., Lee, C., Park, W.S., 1997. Time-dependent equations for wave propagation on rapidly varying topography. Coast. Eng. 32, 91–117.]. The fourth layout type consisting of two parallel lines connected to a semicircle showed the best solutions, especially for a small grid size. This technique is useful for the numerical simulation of irregular waves with broad-banded directional spectrum using conventional spectral wave models for the reasonable estimation of bottom friction and wave-breaking. 相似文献
997.
Seungshic Yum Seonock Woo Man Chang Taek-Kyun Lee Jun-Im Song 《Ocean Science Journal》2005,40(1):55-59
We cloned the complete cDNA of the β-tubulin from the soft coral,Scleronephthya gracillimum (Kükenthal) (Alcyonacea, Octocorallia, Anthozoa, Cnidaria), via the random sequencing of a cDNA library and the 5′-rapid
amplification of cDNA end (RACE) technique. The full-length cDNA of theS. gracillimum β-tubulin comprised 1541 bp, not including the poly (A)+ stretch, also contained a complete open reading frame, which codes for a total of 445 amino acids. The amino acid residues
16-402 appeared to be in a state of conservation in a variety of animals. Northern blot analysis clearly demonstrated that
the sequence we have obtained is, indeed, the full-length cDNA of the β-tubulin gene inS. gracillimum. 相似文献
998.
The process of embryogenesis and larval development of the asteroid sea star Asterias amurensis (Lütken) was observed, with
special attention paid to morphological change and larval duration. In reproductive season, mature sea stars were collected
under floating net cages, located in Tongyeong, southern Korea. The mature eggs are 138 μm in average diameter, semi-translucent
and orange in color, sperms in good condition appear light cream to white-gray in color. Embryos develop through the holoblastic
equal cleavage stage and a wrinkled blastula stage that lasts about 9 hours after fertilization. Gastrulae bearing an expanded
archenteron hatch from the fertilization envelope 22 hours after fertilization. At the end of gastrulation, rudiments of the
left and right coelom are formed. By day 2, larvae possess complete alimentary canal and begin to feed. At this stage, the
larva is called early bipinnaria. In 6day-old larvae, the pre- and post- oral ciliated bands form complete circuits and the
bipinnarial processes start to develop. By day 12, the lateral and anterior projection of the larval wall processes along
the ciliated bands begins to thicken and curl, and the ciliated bands become more prominent. By day 32, early brachiolaria
are presented with three pairs of brachiolar arms. Advanced brachiolaria with a well-developed brachiolar complex (three pairs
of brachia and central adhesive disc) occur 6 weeks after fertilization. In the field, spawning of the sea star was observed
in April to May, settlement form larvae and just settlements seem to occur from June to July, and early juveniles occur from
August to September. Although we had not described the end of brachiolaria stage, it can be tentatively estimated that the
duration of the pelagic stage of A. amurensis is 40 to 50 days. 相似文献
999.
1000.
Analytical models for predicting wave reflection from a perforated-wall caisson breakwater have been developed. Most of the existing models deal with the case in which the waves are normally incident to the caisson lying on a flat sea bottom. In the present paper, using the Galerkin-eigenfunction method, an analytical model is developed that can predict the reflection coefficient of a perforatedwall caisson mounted on a rubble mound foundation when waves are obliquely incident to the breakwater at an arbitrary angle. The developed model is compared with other theoretical results and hydraulic experimental data. 相似文献