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71.
To analyze the development of pine ecosystems on lignite and pyrite containing mine soils, four pine stands with ages of 3–35 years were investigated in a chronosequence approach. Bulk precipitation, throughfall and soil solution in depths of 20, 40, 70 and 100 cm were studied over a three-year period to determine element fluxes in these forest ecosystems on extreme acidic and saline soils.Element budgets are controlled by the processes induced by pyrite oxidation such as intensive weathering of primary minerals, precipitation and leaching of secondary phases.Despite low water fluxes, element outputs can reach extraordinary high values due to very high concentrations in the soil solution. Although element outputs decrease drastically with stand age, respectively, site age, they exceed those of comparable pine stands on non-mine sites. Nitrogen release from the lignite fraction represents a special characteristic of the examined substrates. Nitrogen losses beneath the rooted zone can be 34 kg N ha−1 yr−1 in 100 cm depth. Element input and output in the examined ecosystems are far from balance. Closed cycling of nutrients seems to be recognizable in the case of potassium.  相似文献   
72.
73.
With this petrographic re-investigation of the beerbachite (Chelius, 1892) from Odenwald/Germany geochemical and phase-petrological data are given for the first time.By petrofabric relics (Fig. 7) and geochemical characteristics (Figs. 8–11) is shown that the beerbachite-xenoliths are due to blocks broken down from the surrounding amphibolite series. They are present high grade hornfelses.Beerbachite, porphyroblastic by plagioclase (here porphyroblastic beerbachite, Bbp) (Chelius' Gabbroporphyrit) (Fig. 6) frequently forms marginal zones of beerbachite blocks and is explained as beerbachite-metablastite.Phase relation (Fig. 13) and mineral reactions with increasing metamorphic grade from amphibolite to amphibolite-hornfels (containing hornblende) finally to beerbachite are demonstrated and discussed.The first step may be the mineral reaction: plagI(An 35–40)+hblI+sphene= plagII(An 50–60)+hblII+cpx+opx+magnetite/ilmenite+H2O. The pyroxene-hornfels facies respectively the orthopyroxene subfacies of the K-feldspar-cordierite-hornfels facies (Winkler, 1967) is only reached with the typical assemblage: plag(An 55–70)-cpx-opx-mt/ilm±(quartz) of beerbachite.On condition that the load correspondends to 3–4 km the maximum temperatures may not have exceeded 720–750° C. This valuation would result from experimental data of Choudhuri and Winkler (1967) of the model reaction: hbl=en+di+an+H2O, if . The natural conditions will differ from this experimental model because of resp. P load (p. 81)The very probably required temperature for the mineral assemblage of beerbachite would still be within sub-solidus temperatures of the corresponding model system, according to Fig. 13d. Therefore, the coarse grained plagioclases of Bbp (p. 69) could not be formed from cotectic pockets, too.Finally, convergences and divergences to the beerbachite concept are discussed out of the recent literature.

Herrn Dr. E. Knauer vom hiesigen Institut danken wir sehr für die Bestimmung des Chemismus zweier Pyroxen-Paare aus Beerbachit bzw. Hornfels mit der Mikrosonde (CAMEGA MS 46), Leihgabe der Deutschen Forschungsgemeinschaft. Den Herren Prof. E. Nickel und Dr. M. Maggetti vom Mineralogischen Institut der Universität Fribourg (Schweiz) und Dr. H. D. Trochim, Mineralogisches Institut der Universität Bochum, verdanken wir Vergleichsproben oder Einsichtnahme in vorhandene Dünnschliffe.  相似文献   
74.
Zusammenfassung Eine statistische Analyse der geophysikalischen Potentialfelder, die durch Intensität und Frequenz der regionalen Anomalien bestimmt werden, liefert interessante Ergebnisse über die Struktur der Erdkruste. Im einzelnen können die Tiefe von horizontalen Diskontinuitäten, die Lage von vertikalen tektonischen Störungen, tektonische Vorzugsrichtungen als mittlere Richtungen der Anomalientrends und die mittlere Tiefe derCurie-Isotherme bestimmt werden. Die Grundlage der statistischen Untersuchungen stellt die Korrelationsanalyse dar. Die verschiedenen Methoden werden im einzelnen beschrieben.
Summary A statistical analysis of the geophysical potential fields, which are characterized by intensity and frequency ofthe regional anomalies, shows interesting results on the structure of the crust. Especially there may be determined the depth of horizontal discontinuities, tectonicmean directions as mean directions of anomaly trends and the mean depth of theCurie-point. The basis of the statistical investigations is the correlation-analysis. The several treatments are described in detail.


Mitteilung aus dem Geomagnetischen Institut der DAW, Potsdam, Nr. 264.  相似文献   
75.
Zusammenfassung Der Fund vonPeltoceratoides instabiliformis n. sp. in Steinbrüchen am Gehn nordwestlich von Osnabrück (Abb. 3) liefert weitere Kriterien, daß der Wiehengebirgssandstein, dessen stratigraphische Stellung wegen Mangel charakteristischer Fossilien unsicher ist, ins höhere Oxfordium zu stellen ist. Diese grobklastische Fazies vertritt im Wiehengebirge im wesentlichen die für das Wesergebirge typische kalkige Fazies des Korallenooliths. Anschließend wird zu einer neueren paläogeographischen Mitteilung über den Korallenoolith Nordwestdeutschlands kurz Stellung genommen.
In quarries at the Gehn NW of Osnabrück, several specimens ofPeltoceratoides instabiliformis n. sp. have been found. This gives further indications to the stratigraphic position of the Wiehengebirgs sandstone — which is uncertain, due to the lack of characteristic fossils — to be of Upper Oxfordian age. In the Wiehengebirge though, this coarse clastic facies substitutes to a large extent the calcareous facies of the Korallenoolith typical for the Wesergebirge.A recent paleogeographic report on the Korallenoolith of NW-Germany is then briefly discussed.

Résumé LesPeltoceratoides instabiliformis n. sp. découverts dans des carrières du Gehn au nord-ouest d'Osnabrück fournissent d'autres indices affirmant que le grès du Wiehengebirge dont la position stratigraphique est incertaine faute de fossiles caractéristiques doit être attribué à l'Oxfordien supérieur. Dans le Wiehengebirge, ce faciès clastique à grain grossier remplace dans l'essentiel le faciès calcaire du Korallenoolith typique pour le Wesergebirge.Il suit une brève critique d'une communication paléogéographique récemment parue sur le Korallenoolith du Nord-Ouest de l'Allemagne.

. Peltoceratoides instabiliformis n. sp. . . , . - .


Herrn Professor Dr.Roland Brinkmann zum 70. Geburtstag gewidmet.  相似文献   
76.
Zusammenfassung Es wird gezeigt, daß in den höheren Breiten zwischen dem ozeanischen Stromfeld und der Windverteilung beträchtliche Unterschiede bestehen. Daher wird als Ursache des Strömungssystems nicht das Windfeld, sondern die Süßwasserzufuhr vom Festland angesehen, welche als Salzgehaltsstörung das küstennahe Massenfeld beherrscht und entsprechend dem Theorem nach Bjerknes ein Gradientstromsystem bedingt, welches dem beobachteten entspricht.
A contribution to the system of ocean currents in the higher latitudes
Summary It is demonstrated that in the high latitudes, considerable differences exist between the oceanic current system and the wind distribution. It is, therefore, supposed that it is not the windfield that gives rise to the existing current system but the supply of fresh water from the continent which, as a salinity disturbance, plays a dominant part in the field of mass near the coast. According to Bjerknes' theorem, the disturbance of salinity conditions a gradient current system; this is in good agreement with the observations.

Sur le système de courants marins par les hautes latitudes
Résumé On montre qu'il existe par les hautes latitudes de différences considérables entre le système de courants océaniques et la distribution des vents. Pour cette raison, on suppose que c'est l'afflux d'eau douce venant du continent et non le champ du vent qui engendre le système de courants dominant, sous la forme d'une perturbation de salinité, le champ de masse près des côtes. D'après le théorème de Bjerknes le système de courants de gradient est la conséquence nécessaire de la perturbation de salinité ce qui est en bon accord avec les observations faites dans ce domaine.
  相似文献   
77.
NOAA 8210 has been a region showing a remarkable level of activity well before solar maximum. Dominated by a large, rapidly rotating spot, it produced several intense flares during its disk passage at the end of April–beginning of May 1998. We examine the development of AR 8210 in H and white light (WL) and study the evolution of its complex magnetic topology. While the other principal flares are briefly reviewed, the great X1.1/3B flare of 2 May, which was observed at Kanzelhöhe Solar Observatory during a SOHO/UVCS ground support campaign, is studied in detail. This event has been documented in full-disk H and Na-D intensitygrams, Dopplergrams, and magnetograms, with a time cadence of one minute each. The flare was associated with a CME and produced significant geomagnetic effects. Furthermore, we point out the perspectives for our planned Flare Monitoring and Alerting System, since the two new instruments (Magneto-Optical Filter and Digital H camera), which made their first operational run with the campaign, are crucial components for this program.  相似文献   
78.
The sublimation of water in the region of extremely low pressures and temperatures meets increasing interest for the exploration of icy cosmic bodies. At temperatures below 130 K, the shape of the sublimation curve of H2O is not known; neither experimental data nor theoretical treatments exist for this region. Based upon theoretical upper and lower bounds for the heat capacity of water vapor in this range, a narrow region in the pressure-temperature diagram is identified which must necessarily enclose the sublimation curve down to virtually any lower pressures and temperatures. Within this region, an approximate sublimation curve is computed from the 2006 Gibbs potential of ice Ih, using available heat capacity data points of water vapor between 10 and 130 K. The theoretical zero-point limiting law of the sublimation pressure is derived. Valid between 20 and 273.16 K, correlation equations for the sublimation enthalpy and the sublimation pressure are fitted to the computed data. All quantities are expressed in the 1990 temperature scale ITS-90. Under cosmic conditions, our results suggest that the sublimation of ice is unlikely below 50 K and impossible below 23 K.  相似文献   
79.
The development of instrumental analytics such as the LC-MS/MS has made it possible to quickly determine many component concentrations in a single chromatogram. However, the validation of such multi-methods needs new strategies for robustness and optimization. Statistical execution of analytical tests is one tool that can be utilized to meet this requirement. A Central Composite Design (CCD) was utilized for the validation of an LC-MS/MS multi-method for 84 analytes. The experimental design includes six design variables and two non-design variables (response variables). Concentration, ionization temperature, dwell time, gradient, flow (of eluent), and spraying/curtain gas (continuous design variables) were varied on five different levels; the whole design encompassed 91 runs. To investigate the robustness of a LC-MS/MS method both peak sensitivity and chromatographic separation had to be verified. Therefore, two non-design variables were necessary. The distribution of the peaks over analysis time was applied to describe the quality of the chromatographic separation. The sensitivity was described with the signal to noise ratio (S/N). The evaluation of the measured data was accomplished with the Analysis of Variance (ANOVA) and the Response Surface Methodology (RSM). Three main effects (concentration, ionization temperature, dwell time) and no significant interaction effect were found for the response variable “S/N”. The variables of concentration, ionization temperature, and dwell time had no significant effects for the response variable “S/N”. The ANOVA of the response variable chromatographic separation abandoned no significant effects as well. Therefore, robustness of the method can be guaranteed for all non significant design variables.  相似文献   
80.
The Surai Khola section in southwest Nepal, a 5000 m continuously exposed record of fluvial sedimentation since Middle Miocene, was revisited for high-resolution magnetostratigraphy in sequences with expected cryptochrons and reversals of the geomagnetic field. Polarity intervals with durations of a few tens of thousands of years are recorded as zones of stable palaeomagnetic directions. Polarity transitions are recorded as zones with complex demagnetization behaviour of specimens in the sedimentary column. Almost antiparallel palaeoremanence directions, residing in different haematite phases in the same specimens, could generally not be separated properly by thermal demagnetization. Differing demagnetization paths for neighbouring specimens during a reversal suggest that measured transitional directions are not true geomagnetic field directions, but rather are generated by the superposition of variable amounts of at least two almost antiparallel components of magnetization. Accompanying studies of recent river sand deposits demonstrate that these sediments acquire a true depositional remanent magnetization (DRM) with considerable inclination errors and scattered directions for individual specimens.  相似文献   
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