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41.
42.
Zusammenfassung In einer früheren Arbeit konnte gezeigt werden, daß das durchFjörtoft bei der graphischen Integration des barotropen Modells zur Rückermittlung des Isohypsenfeldes aus der Vorticityverteilung angewandte Näherungsverfahren, dem gewisse die Allgemeinheit einschränkende Voraussetzungen zugrunde liegen, durch eine statistische Methode mit Erfolg ersetzt werden kann. Der vorliegende Bericht beruht auf den gleichen statistischen Grundlagen, es kommen jedoch zusätzlich noch kinematische Überlegungen hinzu, die schließlich zu einer weiteren Vereinfachung des Arbeitsvorganges führen. Auswertungen an einer konkreten Wetterlage zeigen, daß sowohl die statistische wie die statistisch-kinematische Methode darüber hinaus eine gewisse Verbesserung der Resultate der Integration herbeiführen.
Summary In a previous paper it was shown that the computation of the geopotential field from a given vorticity distribution by means of theFjörtoft method of graphical integration of the barotropic model may be improved by the introduction of statistical considerations. The present paper deals with the same subject, however expanded by kinematical considerations which eventually lead to a further simplification of the routine procedure. The application to an actual weather situation indicates that the statistical as well as the statistical-kinematical method render a certain improvement of the results.

Résumé Dans une précédente étude, on avait montré que le processus d'approximation deFjörtoft permettant par intégration graphique de restituer le champ d'isohypses et qui supposait certaines restrictions, peut être remplacé avec succès par une méthode statistique. On ajoute ici à cette dernière des considérations d'ordre cinématique qui conduisent à simplifier encore le procédé. Un exemple pratique démontre que l'intégration proposée conduit à des résultats encore meilleurs.


Mit 1 Textabbildung  相似文献   
43.
Zusammenfassung An der Methode wird die physikalische Unwirklichkeit der Zusammenfassung der Monate Januar, Februar, März und November und Dezember des gleichen Kalenderjahres als Winter und die Unterdrückung wesentlicher Zusammenhänge mit dem Sonnenfleckenzyklus durch Bildung übergreifender Fünfjahresmittel bemängelt. Hinsichtlich des Ergebnisses wird die behauptete Ähnlichkeit der erhaltenen Kurven mit der Sonnenfleckenwelle widerlegt.
Summary It is shown that the practice to define the months of January, February, March and November, December of the same calendar year as winter is not justifiable, from a physical point of view. By using running 5-yearly means important relations to the cycle of sun-spots are suppressed. A proposed similarity of the curves obtained byDammann with the solar cycle is disproved.

Résumé L'auteur montre que l'hiver défini par la période de janvier à mars et de novembre à decembre de la même année est une irréalité physique et que l'emploi de la moyenne mobile de cinq ans masque le cycle des taches solaires; les courbes obtenues parDammann ne correspondent pas rythme des taches.
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44.
Clints are corrasional features with rock inclined to develop karstic forms which originated by the directed run-off of flowing water. The most typical and far spread features occur in the Northern Calcareous Alps where they are marked by their optimum distribution within the former glaciated areas. With few exceptions, the clints occurring in the Alps are recent. Their age can be established as Late- to Post-Glacial. On the whole the karstic features extend from the highest summits deep down into the valleys but a zone of most extensive distribution occurs between 1900–2000 m and 1200–1300 m. The upper limit is controlled by mechanical weathering, the lower limit by the variation of the conditions of run-off below the soil and vegetation cover. As to ecology the total clint zone can be divided into two areas:
  1. The zone of free development of the karst (sharp edged features) and
  2. The zone of subcutaneous karst development (rounded features).
With the formation of the clints the rock acts as modifying factor, but the real forming is controlled only by free run-off conditions.  相似文献   
45.
Zusammenfassung In den Karawanken, die man als jüngstes Gebirge der Ostalpen bezeichnen darf, beobachtet man Hangbrekzien beträchtlichen Ausma\es, deren Absatz unter den heutigen Geländeverhältnissen kaum zu erklären ist. Sie werden einzeln beschrieben und versuchsweise in die Mindel-Ri\-Zwischeneiszeit gestellt.Die Annahme jüngster Verstellungen erleichtert die Erklärung der sonderbaren Lage der Hangbrekzien. Das Gebirge scheint seit jenem Interglazial wesentlich höher geworden zu sein; hierbei spielt der Vorschub gegen Norden eine Rolle.  相似文献   
46.
Zusammenfassung Der Winter 1952/53 war an den deutschen Küsten ein mä\iger Eiswinter. Innerhalb der Winter von 1896/97 bis 1952/53 nimmt er nach seinem Eisausma\ gerade den Zentralwert ein. Während des Winters war die méridionale Luftzirkulation vorherrschend, aber auch der Anteil der zonalen Zirkulation war nicht gering. Unter den Gro\wetterlagen überwogen das abgeschlossene Hoch über Mitteleuropa und die Hochdruckbrücke über Mitteleuropa. Der Winter hatte vier Eisperioden, von denen die zweite nur andeutungsweise auftrat, während die letzte das meiste Eis brachte.
Ice conditions on the German coasts between the rivers Ems and Trave during the winter 1952/53
Summary The winter 1952/53 on the German coasts was a moderate ice winter. Because of the extent of its ice formation it occupies the central value among the winters from 1896/97 up to 1952/53. During this winter, meridional atmospheric circulation predominated, though the part that fell to zonal circulation was not inconsiderable either. Among the large scale weather situations, the closed high pressure area and the ridge of high pressure over Central Europe were preponderant. There were four periods of ice formation of which the second period was but very insignificant, while the greatest ice production was observed during the last cold period.

Rapport sur les conditions des glaces sur les cÔtes allemandes entre l'Ems et le Trave pendant l'hiver 1952/53
Résumé L'hiver 1952/53 sur les cÔtes allemandes montrait un caractère modéré. Parmi les hivers de la période de 1896/97 jusqu'à 1952/53 il occupe justement la valeur centrale à cause de la grandeur de sa production des glaces. Pendant cet hiver, la circulation atmosphérique méridionale prédominait, mais la part de la circulation zonale n'était pas petite non plus. Parmi les situations météorologiques générales, l'aire concentrée de haute pression et la dorsale de haute pression au dessus de l'Europe Central étaient prépondérantes. Il y avait quatre périodes des glaces pendant cet hiver; au cours da la seconde période la production des glaces était insignifiicante tandis que la dernière période était caractérisée par la plus forte formation des glaces.
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47.
Thirty-two weather diaries written in astronomical calendars in central Europe in the late fifteenth and sixteenth centuries are presented and discussed. Systematic weather observations were promoted by the rise of planetary astronomy and its application in astro-meteorology. The practice of keeping weather diaries spread from Cracow (Poland) to Ingolstadt (Germany) and from there to other universities. The data obtained from these sources provided the backbone for setting up series of precipitation indices for Poland, Germany and Switzerland. Monthly statistics of days with precipitation, snowfall and frost were computed by counting the relevant entries in the most important diaries. The results were compared with either those obtained from instrumental measurements in the same place or with those from modern instrumental measurements in a neighbouring place. The final results show that autumn was considerably colder in the early sixteenth century. April was considerably drier and July was wetter during the period 1508-1531 than during 1901-1960. In order to highlight the impact of weather patterns on grain prices in a year of crisis, the timing of wet and dry spells in southern Poland and southern Germany is compared for the year 1529. Winters became 1.7°C colder from 1564 to 1576 and the month of July tended to be wetter than in 1901-1960. Details noted in the diaries kept between 1585 and 1600 by the astronomers Brahe (near Copenhagen) and Fabricius (in the Ostfriesland region of northwestern Germany) closely agree. It rained more often in June and July and temperatures dropped. The winter months were more frequently dominated by winds from easterly directions, the frequency of snowfall was higher and a deficit occurred in precipitation. This points to a higher frequency of high pressure in the Fennoscandian area with cold air advection from the east or northeast.  相似文献   
48.
Sr–Nd–Pb isotope ratios of alkaline mafic intra-plate magmatism constrain the isotopic compositions of the lithospheric mantle along what is now the eastern foreland or back arc of the Cenozoic Central Andes (17–34°S). Most small-volume basanite volcanic rocks and alkaline intrusive rocks of Cretaceous (and rare Miocene) age were derived from a depleted lithospheric mantle source with rather uniform initial 143Nd/144Nd ( 0.5127–0.5128) and 87Sr/86Sr ( 0.7032–0.7040). The initial 206Pb/204Pb ratios are variable (18.5–19.7) at uniform 207Pb/204Pb ratios (15.60 ± 0.05). A variety of the Cretaceous depleted mantle source of the magmatic rocks shows elevated Sr isotope ratios up to 0.707 at constant high Nd isotope ratios. The variable Sr and Pb isotope ratios are probably due to radiogenic growth in a metasomatized lithospheric mantle, which represents the former sub-arc mantle beneath the early Palaeozoic active continental margin. Sr–Nd–Pb isotope signatures of a second mantle type reflected in the composition of Cretaceous (one late Palaeozoic age) intra-plate magmatic rocks (143Nd/144Nd  0.5123, 87Sr/86Sr  0.704, 206Pb/204Pb  17.5–18.5, and 207Pb/204Pb  15.45–15.50) are similar to the isotopic composition of old sub-continental lithospheric mantle of the Brazilian Shield.

Published Nd and Sr isotopic compositions of Mesozoic to Cenozoic arc-related magmatic rocks (18–40°S) represent the composition of the convective sub-arc mantle in the Central Andes and are similar to those of the Cretaceous (and rare Miocene) intra-plate magmatic rocks. The dominant convective and lithospheric mantle type beneath this old continental margin is depleted mantle, which is compositionally different from average MORB-type depleted mantle. The old sub-continental lithospheric mantle did not contribute to Mesozoic to Cenozoic arc magmatism.  相似文献   

49.
We report the discovery of the most complex arcsec-scale radio gravitational lens system yet known. B1933+503 was found during the course of the CLASS survey and MERLIN and VLA radio maps reveal up to 10 components. Four of these are compact and have flat spectra; the rest are more extended and have steep spectra. The background lensed object appears to consist of a flat-spectrum core (quadruply imaged) and two compact 'lobes' symmetrically disposed relative to the core. One of the lobes is quadruply imaged while the other is doubly imaged. An HST observation of the system with the WFPC2 shows a galaxy with an axial ratio of 0.5, but none of the images of the background object is detected. A redshift of 0.755 has been measured for the lens galaxy.  相似文献   
50.
A sample of 47 faint Gigahertz Peaked Spectrum (GPS) radio sources selected from the Westerbork Northern Sky Survey (WENSS) has been imaged in the optical and near-infrared, resulting in an identification fraction of 87 per cent. The R  −  I R  −  K colours of the faint optical counterparts are as expected for passively evolving elliptical galaxies, assuming that they follow the R -band Hubble diagram as determined for radio-bright GPS galaxies. We find evidence that the radio spectral properties of the GPS quasars are different from those of GPS galaxies. The observed distribution of radio spectral peak frequencies for GPS sources optically identified with bright stellar objects (presumably quasars) is shifted compared with GPS sources identified with faint or extended optical objects (presumably galaxies), in the sense that a GPS quasar is likely to have a higher peak frequency than a GPS galaxy. This means that the true peak frequency distribution is different for the GPS galaxies and quasars, because the sample selection effects are independent of optical identification. The correlation between peak frequency and redshift that has been suggested for bright sources has not been found in this sample; no correlation exists between R magnitude (and therefore redshift) and peak frequency for the GPS galaxies. We therefore believe that the claimed correlation is actually caused by the dependence of the peak frequency on optical host, because the GPS galaxies are generally at lower redshifts than the quasars. The difference in the peak frequency distributions of the GPS galaxies and quasars is further evidence against the hypothesis that they form a single class of object.  相似文献   
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