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41.
Andrea I. Pasquini Stella M. Formica Gabriela A. Sacchi 《Environmental Earth Sciences》2012,65(2):453-467
Suquía River is a medium-sized hydrological system (basin area of ~7,700 km2) that supplies fresh water to Córdoba city, a town of ~1,500,000 inhabitants in central Argentina. This paper examines the
present-day hydrochemistry of Suquía River urban catchment analyzing its major and minor dissolved components, and the nutrients
variability by means of QUAL-2K modeling software. The Suquía River has bicarbonate-type waters upstream the city and sulfate-type
waters right downstream, whereas they exhibit a mixed-to-alkali-type cationic composition. The seasonal analysis of its major
dissolved constituents clearly showed a dilution process during the wet season (i.e. austral summer). In the last 20 years,
the Suquía River has modified its anionic composition, now showing higher relative concentrations of SO4
2− as a consequence of urban activities. However, trace elements dissolved concentrations do not evidence a strong pollution
effect. Nutrients [nitrogen species, total phosphorous (TP)] and related parameters, such as biochemical oxygen demand (BOD),
and dissolved oxygen (DO), evidence a clear influence of human activities. The QUAL-2K model was used to evaluate the spatial
behavior of selected nutrients and associated variables, (i.e. TP, N–NH4
+, N–NO3
−, DO, BOD). Nutrient concentrations are affected by point sources of contaminants, particularly domestic waste and sewage,
as well as by diffuse agricultural pollution. A calibrated QUAL-2K modeling exercise clearly shows the impact of the Córdoba
city’s municipal wastewater treatment plant on the Suquía River water quality. 相似文献
42.
Budzyń Bartosz Harlov Daniel E. Kozub-Budzyń Gabriela A. Majka Jarosław 《Mineralogy and Petrology》2017,111(2):183-217
Mineralogy and Petrology - The relative stabilities of phases within the two systems monazite-(Ce) – fluorapatite – allanite-(Ce) and xenotime-(Y) – (Y,HREE)-rich fluorapatite... 相似文献
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Sergio Archangelsky Viviana Barreda Mauro G. Passalia Maria Gandolfo Mercedes Prámparo Edgardo Romero Rubén Cúneo Alba Zamuner Ari Iglesias Magdalena Llorens Gabriela G. Puebla Mirta Quattrocchio Wolfgang Volkheimer 《Cretaceous Research》2009,30(5):1073-1082
In this report, we analyze the angiosperm fossil record (micro- and megafossil) from the central and southern basins of Argentina, southern South America, deposited between the late Barremian (128.3 Ma) to the end of the Coniacian (85.8 Ma). Based on this analysis, three major stages in the evolution of the angiosperms in the southernmost region of South America are established as follows: the late Barremian–Aptian, the latest Aptian-earliest Albian, and the middle Albian- Coniacian. The comparison between our fossil data set and those from Australia, North America, Asia and Europe suggest that the evolution and diversification of the angiosperms at mid and high latitudes in both hemispheres occurred roughly synchronously. 相似文献
45.
Cholinesterases (ChE) from brain, muscle and liver in Nile tilapia (Oreochromis niloticus) were characterized using three substrates: acetylthiocholine iodide, propionylthiocholine iodide, and butyrylthiocholine iodide. Eserine was used as a total ChE inhibitor; BW284c51 and iso-OMPA were used as selective inhibitors for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), respectively. The results indicate that AChE is the enzyme present in brain, whereas in both liver and muscle, the presence of atypical ChEs are suggested. These findings indicate that characterization of ChE is necessary prior to use in monitoring programs. 相似文献
46.
Bianca Mitrică Istvan Bogardi Eugen Mitrică Irena Mocanu Marin Minciună 《Norsk geografisk tidsskrift. Norwegian journal of geography》2017,71(1):12-29
The article examines the risk of water shortages due to the climate change on Leu-Rotunda Plain, which is part of Oltenia Plain in Romania. The region has been exposed to several extreme climatic phenomena, mostly droughts, which has created several problems related to water quality and quantity. The authors defined climate change scenarios using two regional climate models. Water resources under climate change were estimated by a regional numerical groundwater model covering a deep aquifer. The water demand components were estimated for households, industries, services, and livestock, based on specific socio-economic assumptions. A non-probabilistic risk assessment, using simplified fuzzy sets mathematics, was used to estimate water supply, water demand, and the consequences of water shortages. The results of the study revealed significant vulnerability in the water supply, a limited territorial expansion of sewerage networks, an expected increase in households’ demand, an expected increase in industrial and services water demand, a relatively stable demand for water for livestock farming, and an important water shortage in the study area. The authors conclude by highlighting a set of actions to mitigate the risk of the potential crisis. 相似文献
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49.
The false Basel earthquake of May 12, 1021 总被引:1,自引:0,他引:1
Gabriela Schwarz-Zanetti Virgilio Masciadri Donat Fäh Philipp Kästli 《Journal of Seismology》2008,12(1):125-129
The Basel (CH) area is a place with an increased seismic hazard. Consequently, it is essential to scrutinize a famous statement by Stumpf (Gemeiner loblicher Eydgnoschafft Stetten, Landen und Völckeren Chronikwirdiger thaaten beschreybung. Durch Johann Stumpffen beschriben, 1548) that allegedly a large earthquake took place in Basel in 1021. This can be disproved unambiguously by applying historical and philosophical methods. 相似文献
50.
Gabriela González Trilla Silvia De Marco Jorge Marcovecchio Ricardo Vicari Patricia Kandus 《Estuaries and Coasts》2010,33(4):953-962
Coastal marshes are known as organic matter producers. The goal of this work is to study tiller demography, standing biomass, and net aerial primary productivity (NAPP) in a Spartina densiflora coastal wetland, using a method applied to permanent sample plots located at two sites differing in topographic location, a regularly flooded zone [relative low marsh (LM)] and an irregularly flooded one [relative high marsh (HM)]. Measurements were made every 2 months during the 2005–2007 period. The annual NAPP was estimated to be 2,599?±?705 gDW m?2?year?1 for the HM and 2,181?±?605 gDW m?2?year?1 and 602?±?154 gDW m?2?year?1 for the first and second period of the LM populations, respectively, showing a seasonal pattern reaching maximum values in summer. The reduced NAPP values of the LM sites in the second year was associated with an extremely high precipitation period related to the 2007–2008 El Niño event. 相似文献