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961.
DECOVALEX Project: from 1992 to 2007 总被引:3,自引:0,他引:3
The DECOVALEX project is a unique international research collaboration, initiated in 1992, for advancing the understanding
and mathematical modelling of coupled thermo-hydro-mechanical (THM) and thermo-hydro-mechanical-chemical (THMC) processes
in geological systems—subjects of importance for performance assessment of radioactive waste repositories in geological formations.
From 1992 up to 2007, the project has made important progress and played a key role in the development of numerical modelling
of coupled processes in fractured rocks and buffer/backfill materials. The project has been conducted by research teams supported
by a large number of radioactive-waste-management organizations and regulatory authorities, including those of Canada, China,
Finland, France, Japan, Germany, Spain, Sweden, UK, and the USA. Through this project, in-depth knowledge has been gained
of coupled THM and THMC processes associated with nuclear waste repositories, as well as numerical simulation models for their
quantitative analysis. The knowledge accumulated from this project, in the form of a large number of research reports and
international journal and conference papers in the open literature, has been applied effectively in the implementation and
review of national radioactive-waste-management programmes in the participating countries. This paper presents an overview
of the project. 相似文献
962.
Granulometric analysis of nineteen sediment samples has been carried out for their statistical and textural parameters. The
samples are collected from the northern and southern margins of Schirmacher Oasis extending below the polar ice sheet and
grading to coastal area respectively and main rocky land of Schirmacher including lakes. The analysis shows that most of the
sediments are of medium grain size and fall in poor to very poor sorted category.
An attempt has been made to interpret the depositional set-up by plotting the scatter patterns between various textural parameters,
including C-M plot and arithmetic log-probability curves. The influence of physical parameters viz. low to high velocity winds,
ice and meltwater on sediment characteristics has been discussed. 相似文献
963.
The Urban Seismic Risk index (USRi) published in a previous article (Carreño et al., Nat Hazards 40:137–172, 2007) is a composite indicator that measures risk from an integrated perspective and guides decision-making for identifying the main interdisciplinary factors of vulnerability to be reduced or intervened. The first step of the method is the evaluation of the potential physical damage (hard approach) as a result of the convolution of the seismic hazard with the physical vulnerability of buildings and infrastructure. Subsequently, a set of social context conditions that aggravate the physical effects is also considered (soft approach). According to this procedure, the physical risk index is evaluated for each unit of analysis from existing loss scenarios, whereas the total risk index is obtained by multiplying the former index by an impact factor using an aggravating coefficient, based on variables associated with the socio-economic conditions of each unit of analysis. The USRi has been developed using the underlying holistic and multi-hazard approach of the Urban Risk Index framework proposed for the evaluation of disaster risk in different megacities worldwide. This article presents the sensitivity analysis of the index to different parameters such as input data, weights and transformation functions used for the scaling or normalization of variables. This analysis has been performed using the Monte Carlo simulation to validate the robustness of this composite indicator, understanding as robustness how the cities maintain the ranking as well as predefined risk level ranges, when compared with the deterministic results of risk. Results are shown for different cities of the world. 相似文献
964.
K. R. Praveen V. Prasannakumar Manish A. Mamtani 《Journal of the Geological Society of India》2009,73(6):803-812
Anisotropy of magnetic susceptibility (AMS) is investigated in samples of Peralimala (PM) pluton (ca. 550 Ma) and adjacent
gneiss, gabbro, mylonite and amphibolite from the Moyar Shear Zone (MSZ), Southern Granulite Terrane (SGT) with an aim to
decipher the time-relationship between fabric development in the pluton and regional tectonics. Magnetic foliation recorded
in the PM pluton is sub-parallel to the WNW-ESE striking MSZ. Magnetic foliation and lineation trajectories are sigmoidal
and curve into the shear zone. A dextral sense of shear is deciphered from the trajectories, which is similar to that reported
within the MSZ in some earlier studies. It is inferred that the PM pluton has developed post-emplacement deformation-fabric
related to reactivation of the MSZ during Pan-African age. Based on the data and existing information about regional tectonics
of the area, the possibility of the (a) PM pluton being a Deformed Alkali Rock and Carbonatite (DARC) and (b) MSZ marking
an ancient suture zone, is discussed. 相似文献
965.
John Finn 《GeoJournal》2009,74(3):191-200
After more than three decades of isolation from the West and a paralyzing economic crisis in the early 1990s, Cuba is increasingly
globally active in both cultural and economic realms. In this paper I use Bourdieu’s (The fields of cultural production, 1993)
fields of cultural production as a general frame through with to inspect the commercialization of Cuban music. Through a case
study with Juan de Marcos Gonzalez, the creator of the Buena Vista Social Club, I explore the dialectical relationship of
music as an expression of cultural and a cultural asset, and at the same time a commodity for the international market. I
show that de Marcos uses his position between the international music industry and the local music scene in order to preserve
cultural authenticity and survive economically. In doing so he challenges the all-to-typical place of the artist in the contested
space of cultural production between the West and the Third World.
相似文献
John FinnEmail: |
966.
Agricultural practices, hydrology, and water quality of the 267-km2 Big Spring groundwater drainage basin in Clayton County, Iowa, have been monitored since 1981. Land use is agricultural; nitrate-nitrogen
(-N) and herbicides are the resulting contaminants in groundwater and surface water. Ordovician Galena Group carbonate rocks
comprise the main aquifer in the basin. Recharge to this karstic aquifer is by infiltration, augmented by sinkhole-captured
runoff. Groundwater is discharged at Big Spring, where quantity and quality of the discharge are monitored.
Monitoring has shown a threefold increase in groundwater nitrate-N concentrations from the 1960s to the early 1980s. The nitrate-N
discharged from the basin typically is equivalent to over one-third of the nitrogen fertilizer applied, with larger losses
during wetter years. Atrazine is present in groundwater all year; however, contaminant concentrations in the groundwater respond
directly to recharge events, and unique chemical signatures of infiltration versus runoff recharge are detectable in the discharge
from Big Spring.
Education and demonstration efforts have reduced nitrogen fertilizer application rates by one-third since 1981. Relating declines
in nitrate and pesticide concentrations to inputs of nitrogen fertilizer and pesticides at Big Spring is problematic. Annual
recharge has varied five-fold during monitoring, overshadowing any water-quality improvements resulting from incrementally
decreased inputs.
Electronic Publication 相似文献
967.
Kozlov V. I. 《GeoJournal》1980,4(1):23-30
The paper deals with the processes of ethnic consolidation, ethnic and linguistic assimilation and inter-ethnic integration taking place in the USSR. The author shows the influence of consolidation and assimilation processes over the trends in the numerical strength of individual peoples and the resulting change in the country's ethnic composition as this is reflected in the Soviet population censuses of 1926, 1959, 1970, and 1979. 相似文献
968.
From the studies of ore deposit geologic settings,sulfur isotopes,lead isotopes,carbon isotopes and oxygen isotopes,fluid inclusions and petrochemistry in this paper,the authors have drawn a conclusion that the ore-forming hydrothermal solutions are the high-temperature magmatic hydrothermal solutions for the gold ore deposit,and at the same time,the involvemety of crustal materials can not be ruled out .It is the first time that the authors have proposed that the Laozuoshan gold-ploymetallic ore deposit in Heilongjiang Province was formed in the calc-alkaline series environment at the margin of an active continent. 相似文献
969.
1IntroductionLanmuchangite ,anewmineralTlAl[SO4]2 ·1 2H2 O ,occursintheoxidationzoneofrichthalli umorebodiesattheLanmuchangthallium(mercury)deposit.Itisnamedafterthelocalitywhereitwasdiscovered .InJune,2 0 0 1 ,themineralanditsnamewereapprovedbytheCommissiononNewMineralsandMineralNames,IMA .ItstypicalmaterialisdepositedattheGeologicalMuseumofChina ,Beijing .2OccurrenceandmineralassociationLanmuchangiteoccursintheoxidationzoneofrichthalliumorebodiesattheLanmuchangthal lium(mercury)or… 相似文献
970.
Ernst-Dieter Hornig 《Geotechnical and Geological Engineering》2010,28(3):233-240
Measured settlements of buildings on the weathered Keuper Marl appeared to be much smaller than calculated settlements, which
were based on stiffness modulus from standard oedometer tests. Therefore, both special triaxial K
0-tests and oedometer tests were carried out for an accurate determination of stiffness moduli. Modulus obtained in the triaxial
K
0-tests were at least two to three times the values obtained in the oedometer tests. To verify observations from the laboratory
tests, the loads and the settlements of two single footings on weathered Keuper mudstone have been measured during construction
of a building over 1 year. Also, a large scale footing load test with measurements of deformations were conducted on the weathered
Keuper mudstone. The measured settlements of the two single footings and the tested foundation were compared with the settlements
based on conventional calculations with moduli from oedometer tests and triaxial K
0-tests. Up to a foundation pressure of σv = 500 kN/m2 the calculated settlement based on E
S-modulus obtained from triaxial K
0-tests was found to correspond well to the measured deformation. For foundation pressure beyond 500 kN/m2, the foundation
response was highly non-linear and it could not be described any more with the linear-elastic model. Therefore the footing
load test was also simulated by FEM analyses. 相似文献