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排序方式: 共有613条查询结果,搜索用时 437 毫秒
431.
Anna Maria Szczucińska Marcin Siepak Anetta Zioła-Frankowska Marek Marciniak 《Environmental Earth Sciences》2010,61(5):921-930
Groundwater outflows (springs and seeps) from porous sediments on European lowlands play a significant role in the surface
water balance. It is therefore important to document these outflows’ water quality and spatial and temporal changes. The present
study focused on changes in iron, manganese, and heavy metals in waters of groundwater outflows in an area of low anthropogenic
impact—the Gryżyna-Grabin Tunnel Valley in western Poland. Eleven outflows were studied for a period of 2 years. Most of the
samples analyzed revealed low element contents and little variation in time and space. Only values of iron and lead were above
World Health Organization limits for drinking water. The concentrations of these elements were also variable in time and space.
The seasonal changes in iron content are probably due to natural, temperature- and pH-controlled reactions of shallow groundwater
with aquifer sediments. On the other hand, the elevated lead content points to regional water contamination. 相似文献
432.
Study of litter influence on magnetic susceptibility measurements of urban forest topsoils using the MS2D sensor 总被引:1,自引:1,他引:0
Jarosław Zawadzki Piotr Fabijańczyk Tadeusz Magiera Zygmunt Strzyszcz 《Environmental Earth Sciences》2010,61(2):223-230
Field magnetometry is fast and convenient method used to detect areas contaminated by technogenic magnetic particles and potentially
polluted with heavy metals. Frequently, measurements of soil magnetic susceptibility (κ) are carried out with MS2D Bartington
sensor, which penetration range equals 10 cm, although 90% of the total signal is detected from a depth of up to 6 cm. Thick
uppermost organic soil layers may significantly influence on the measured κ because the penetration range may be not large
enough to cover the layers where the most of anthropogenic contaminants are cumulated. The aim of the study was to investigate
on how the removal of the litter improves the MS2D measurements of soil pollution. Accordingly, the correlations between κ
values measured on the successively removed overlying soil sub-horizons were investigated. Measurements were performed at
15 sites located in different forest in the Upper Silesian Industrial Area, Poland. The results showed that the litter removal
enabled the MS2D to measure the κ more related to the anthropogenic pollution, and did not affect the measuring variance. 相似文献
433.
Marcin Frankowski Anetta Zioła-Frankowska Artur Kowalski Jerzy Siepak 《Environmental Earth Sciences》2010,60(6):1165-1178
The study presents the results of Cu, Pb, Zn, Mn and Fe determination in the samples of bottom sediments collected from the
Oder and Warta rivers. The sequential extraction of metals in the samples of bottom sediments was performed after introducing
the modification of the extraction scheme suggested by Tessier et al. (Anal Chem 51(7):844–851, 1979). The extraction times
of particular stages were optimised. The fifth stage was altered by introducing the new methods of performing extraction.
The samples of bottom sediments submitted the following granulometric analyses: dry, wet and wet with (HMP) dispersing reagent.
Seven granulometric fractions with the following grain sizes were isolated: >2.0, 2.0–1.0, 1.0–0.5, 0.5–0.25, 0.25–0.1, 0.1–0.063
and <0.063 mm. The sequential extraction of particular granulometric fractions was performed. The concentration of metals
variability was analysed depending on the method of sample preparation for the chemical analysis, granulometric fraction of
sediments subjected to the analysis, extraction conditions and the site of samples collection. The lack of linearity between
the metal concentration and the size of granulometric fraction was observed. The highest concentrations of metals were observed
in fractions >2.0, 2.0–1.0 and 0.1–0.063 and <0.063 mm while the lowest concentrations occurred in fractions 1.0–0.5, 0.5–0.25,
and 0.25–0.1 mm. The atomic absorption spectrometry with flame atomisation (F-AAS) was used for the determination of the investigated
elements. 相似文献
434.
435.
Chlorophyll a and its selected derivatives, as well as chlorophylls b and c have been determined in samples of recent (0-10 cm) sediments, collected at 30 stations in the Szczecin Lagoon, Pomeranian Bay and the Bornholm Deep. Samples were retrieved in different seasons between 1992 and 2001, including the time before and after the great flood of July 1997. Regarding the content of chlorophyll a and its derivatives in sediments, the Szczecin Lagoon may be classified as permanently eutrophic and the Pomeranian Bay and Bornholm Deep as mesotrophic. A lack of correlation between chlorophylls b, c and chlorophyll a indicated that intensive blooms of cyanobacteria occur in the Szczecin Lagoon, which is a characteristic of eutrophic zones. The chlorin a results are related to selected parameters characterizing the aquatic environment. The values for nutrients, salinity and temperature in near-bottom waters, as well as granulometry and organic carbon in the sediments verify the above conclusions. 相似文献
436.
437.
Kowalewska G Konat-Stepowicz J Wawrzyniak-Wydrowska B Szymczak-Zyła M 《Marine pollution bulletin》2003,46(6):703-718
This paper describes the transfer of organic contaminants to the sea, using PAHs (12 compounds) and PCBs (11 congeners) as examples, through a eutrophicated coastal lagoon (Szczecin Lagoon, on the Polish-German border). The transfer of contaminants study was based on their concentration in recent sediments (0-10 cm), in relation to different environmental conditions such as temperature, salinity, turbidity, oxygen and nutrients in water, hydrological conditions, organic carbon and biomarkers (pigments and their derivatives) in sediments. Results include the data obtained between 1994 and 2000, also those on before and afterwards the great flood in July 1997, at different stations in the Lagoon and the adjacent Pomeranian Bay. The results indicated that the eutrophic estuary of the shape of lagoon acts as an effective trap for the hydrophobic organic pollutants. The abundance and taxonomy of plankton as well as detritus derived from it play an important role in bonding the studied compounds. The salinity gradient in the lagoon has a significant influence upon deposition of the pollutants from the water column to the sediments and the residence time of the compounds there depends strongly on oxic-anoxic status of the sediments and the strength of interaction with sediments resulting from polarity, the type and stability of associates formed, as well as on hydrological conditions. We conclude that eutrophication in this area prevents pollution of the sea to some extent. 相似文献
438.
Wolfgang Dörr Andrzej Żelaźniewicz Paweł Bylina Janina Schastok Wolfgang Franke Udo Haack Cyprian Kulicki 《International Journal of Earth Sciences》2006,95(2):341-349
The Odra Fault Zone of southwestern Poland is a NW-trending horst marked by gravimetric and magnetic anomalies and composed of high- to low-grade metamorphic and igneous rocks which are only known from boreholes. This zone embraces a concealed border between Variscan internides and externides. It also contains an array of several I-type, metaluminous to peraluminous, high potassic granitoid bodies which intruded earlier metamorphosed rocks. Except for one case, they remain unfoliated and undeformed, and presumably play a role of stitching plutons at the suture between two obliquely colliding terranes. U–Pb TIMS dating of single zircons from one foliated and one unfoliated granitoid samples yielded identical concordant ages of 344±1 Ma (Tournaisian). They resemble a Pb–Pb age of 350±5 Ma obtained for S-type granitoids from the Luckau area further west in Germany, which is generally regarded as an eastern segment of the Mid-German Crystalline High. Carboniferous granitic intrusions in the high are generally younger (340–290 Ma). Correlations of the the Odra Fault Zone with the Mid-German Crystalline High appear plausible, but by no means certain and require further confirmation. 相似文献
439.
Tomisław Gołębiowski 《Acta Geophysica》2006,54(4):413-429
The paper presents the results of georadar investigations carried out in the area of the monastery at Tyniec near Cracow for
archaeological purposes. The georadar profiles were designed on the abbey courtyard in a regular grid, which covered the area
of the buildings that currently do not exist. The aim of the measurements was to produce a 3D visualization of former buildings’
foundation. The results of the geophysical measurements were correlated with the information obtained from archaeological
investigations. The georadar surveys confirmed the location of foundations documented by archeologists and new underground
structures were discovered. To aid the interpretation, numerical modelling of the electromagnetic wave field was performed.
Computer modelling allowed to determine the kind and condition of underground structures. 相似文献
440.
Radosław Tarkowski 《Comptes Rendus Geoscience》2005,337(9):799-805
Industrial sectors responsible for large part of CO2 emissions in Poland are characterized from the point of view of possibilities of sequestration of this gas by underground storage. On the basis of official statistics and data obtained from local administration and individual plants, attempt was made to evaluate the magnitude of emissions from selected categories, sub-categories and sectors of the industry (in accordance with methodology of IPCC), concentration of CO2 in combustion gases and those emitted by industry, and to identify major point sources of emission of this gas in Poland. A special attention was paid to those sectors of industry that may be the first to act as a source of carbon dioxide for sequestration by underground storage in the nearest future. To cite this article: R. Tarkowski, C. R. Geoscience 337 (2005). 相似文献