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231.
232.
Heinrich Hoeber 《Boundary-Layer Meteorology》1989,48(3):293-297
Temperature observations of three buoys drifting in the Weddell Sea for one year and covering the ice-water-ice cycle from July 1986 to July 1987 are presented. Significant differences between winter and summer are shown to be a consequence of the air-sea heat exchange being drastically modified by the sea ice cover. Over ice, prevailing variance is in the synoptic scale (periods 3 to 5 days) with amplitudes of 25 °C, whereas over water, the diurnal wave dominates with amplitudes of less than 1 °C. 相似文献
233.
Heinrich Gundlach Franz Karl Georg Müller 《Contributions to Mineralogy and Petrology》1967,16(4):285-299
Zusammenfassung Im Anschluß an vergleichende Untersuchungen Karls (1959) zur Petrographie und chemischen Zusammensetzung metamorpher Tonalite nördlich des Alpenhauptkammes und nichtmetamorpher Intrusivgesteine des Periadriatischen Bogens wurden für geochemische Untersuchungen insgesamt 113 Gesteinsproben aus beiden Gebieten entnommen.Diese wurden auf folgende Hauptbestandteile: SiO2, Fe ges. (als Fe2O3), CaO, MgO, Na2O und K2O sowie die Spurenelemente: Zn, Co, Ni, V, Cr, Sr, Pb (ferner Cu, Sn und Be) untersucht.Getrennt für beide Gesteinsgruppen wurden aus den Analysendaten die statistischen Mittelwerte und deren Standardabweichungen für die einzelnen Elemente berechnet.Beide Gruppen stimmen innerhalb der Standard-Abweichungen weitgehend überein, d. h. die metamorphen Tonalite der Nord-Gruppe entsprechen bezüglich der gefundenen Spurenelementgehalte den nichtmetamorphen periadriatischen Intrusivgesteinen der Süd-Gruppe. Eine Ausnahme bilden Co und Ni, die in der Nord-Gruppe deutlich höher liegen.Eine Beeinflussung des Spurenelementhaushaltes in den Gesteinen der Nord-Gruppe durch die Metamorphose (Tauernkristallisation) läßt sich nicht folgern. Die Co- und Ni-Gehalte müssen im Norden primär höher gewesen sein, denn die hier gegebenen Mittelwerte der Spurenelemente zeigen im Vergleich mit Werten aus Datensammlungen gute Übereinstimmung und deuten auf ein der Norm saurer Intrusiva entsprechendes geochemisches Milieu hin. Nur das Pb weicht mit erhöhten Werten von der Norm ab. Auch Grohmann (1965) gibt in Analysen vergleichbarer ostalpiner Gesteine erhöhte Pb-Gehalte an.Aus dem stofflich konservativen Verlauf der Tauernkristallisation wird ersichtlich, daß die Bildung der alpinen Lagerstätten dieses Raumes nicht auf die Metamorphose bezogen werden kann.
Unser Dank gilt der Bundesanstalt für Bodenforschung, Hannover, namentlich Herrn Prof. Dr. H. J. Martini und Herrn Prof. Dr. H. R. v. Gaertner, ferner der Deutschen Forschungsgemeinschaft, Bad Godesberg, für die Förderung unserer Arbeit.Herrn Dr. H. Fesser, Bundesanstalt für Bodenforschung, danken wir für die Durchführung spektrographischer Untersuchungen, Frau M. Elstner für Fleiß und Sorgfalt bei den chemischen Arbeiten. 相似文献
Following the comparative studies of Karl (1959) regarding the petrography and the chemical composition both of metamorphic tonalites in the north of the Alpen main ridge and the neighbouring nonmetamorphic periadriatic plutonic rocks in the south, 113 samples were taken from both areas for geochemical investigations. They have been analysed for the following main components: SiO2, Fe2O3 (total Fe), CaO, MgO, Na2O, and K2O as well as for the trace elements Zn, Co, Ni, V, Cr, Sr, Pb, and also Cu, Sn, and Be.The arithmetic means of the analytical data have been calculated separately for the different elements inside both groups. Within the standard deviations the two groups agree with each other, except for Co and Ni, which have distinctive higher values in the Northern group. The dominant conformity of both groups indicates that the trace element content of the Northern group was not changed by the Tauern metamorphism. The contents of Co and Ni must have been primarily higher in the north.Comparisons with corresponding data of trace element contents given in diverse geochemical tables agree well with the values of means given here. Only Pb deviates with higher values from the standard content of acid plutonic rocks. This is in accordance with the results of Grohmann (1965), who also found higher values of Pb in comparative plutonic rocks of the Eastern Alpen mountains.
Unser Dank gilt der Bundesanstalt für Bodenforschung, Hannover, namentlich Herrn Prof. Dr. H. J. Martini und Herrn Prof. Dr. H. R. v. Gaertner, ferner der Deutschen Forschungsgemeinschaft, Bad Godesberg, für die Förderung unserer Arbeit.Herrn Dr. H. Fesser, Bundesanstalt für Bodenforschung, danken wir für die Durchführung spektrographischer Untersuchungen, Frau M. Elstner für Fleiß und Sorgfalt bei den chemischen Arbeiten. 相似文献
234.
235.
M. Schröter A. Obermeier A. Heinrich D. Brüggemann 《Meteorology and Atmospheric Physics》2006,92(3-4):231-238
Summary This paper describes the comparison of calculated extinction coefficients from Lidar signals by the known Fernald-Klett inversion
method with Lidar signal simulations. A ground-based Differential Absorption Lidar was employed in two studies measuring O3 and SO2 within the planetary boundary layer (PBL). By calculating extinction coefficients additional information about the PBL structure
is obtained. As commonly used numerical inversion methods are limited to the knowledge of necessary boundary conditions, Lidar
signal simulations are used for their estimation. Furthermore, comparing results of the inversion method with Lidar signal
simulations validates calculated extinction coefficients. 相似文献
236.
Temperature-dependent isotopic fractionation of lithium between clinopyroxene and high-pressure hydrous fluids 总被引:2,自引:1,他引:2
Bernd Wunder Anette Meixner Rolf L. Romer Wilhelm Heinrich 《Contributions to Mineralogy and Petrology》2006,151(1):112-120
The fractionation of lithium isotopes between synthetic spodumene as representative of Li-bearing clinopyroxene and Cl- and
OH-bearing aqueous fluids was experimentally determined between 500 and 900°C at 2.0 GPa. In all the experiments, 7Li was preferentially partitioned into the fluid. The fractionation is temperature dependent and approximated by the equation
Δ7Li(clinopyroxene–fluid)=−4.61×(1,000/T [K]) + 2.48; R
2=0.86. Significant Li isotopic fractionation of about 1.0‰ exists even at high temperatures of 900°C. Using neutral and weakly
basic fluids revealed that the amount of fractionation is not different. The Li isotopic fractionation between altered basalt
and hot spring water (350°C) in natural samples is in good agreement with our experimentally determined fractionation curve.
The data confirm earlier speculations drawn from the Li isotopic record of dehydrated metamorphic rocks that fluids expelled
from a dehydrating slab carry heavier Li into the mantle wedge, and that a light Li component is introduced into the deeper
mantle. Li and Li isotopes are redistributed among wedge minerals as fluids travel across the wedge into hotter regions of
arc magma production. This modifies the Li isotopic characteristics of slab-derived fluids erasing their source memory, and
explains the absence of cross-arc variations of Li isotopes in arc basalts. 相似文献
237.
Detailed melt and fluid inclusion studies in quartz hosts from the Variscan Ehrenfriedersdorf complex revealed that ongoing fractional crystallization of the highly evolved H2O-, B-, and F-rich granite magma produced a pegmatite melt, which started to separate into two immiscible phases at about 720°C, 100 MPa. With cooling and further chemical evolution, the immiscibilty field expanded. Two conjugate melts, a peraluminous one and a peralkaline one, coexisted down to temperatures of about 490°C. Additionally, high-salinity brine exsolved throughout the pegmatitic stage, along with low-density vapor. Towards lower temperatures, a hydrothermal system gradually developed. Boiling processes occurred between 450 and 400°C, increasing the salinities of hydrothermal fluids at this stage. Below, the late hydrothermal stage is dominated by low-salinity fluids. Using a combination of synchrotron radiation-induced X-ray fluorescence analysis and Raman spectroscopy, the concentration of trace elements (Mn, Fe, Zn, As, Sb, Rb, Cs, Sr, Zr, Nb, Ta, Ag, Sn, Ta, W, rare earth elements (REE), and Cu) was determined in 52 melt and 8 fluid inclusions that are representative of distinct stages from 720°C down to 380°C. Homogenization temperatures and water contents of both melt and fluid inclusions are used to estimate trapping temperatures, thus revealing the evolutionary stage during the process. Trace elements are partitioned in different proportions between the two pegmatite melts, high-salinity brines and exsolving vapors. Concentrations are strongly shifted by co ncomitant crystallization and precipitation of ore-forming minerals. For example, pegmatite melts at the initial stage (700°C) have about 1,600 ppm of Sn. Concentrations in both melts decrease towards lower temperatures due to the crystallization of cassiterite between 650 and 550°C. Tin is preferentially fractionated into the peralkaline melt by a factor of 2–3. While the last pegmatite melts are low in Sn (64 ppm at 500°C), early hydrothermal fluids become again enriched with about 800 ppm of Sn at the boiling stage. A sudden drop in late hydrothermal fluids (23 ppm of Sn at 370°C) results from precipitation of another cassiterite generation between 400 and 370°C. Zinc concentrations in peraluminous melts are low (some tens of parts per million) and are not correlated with temperature. In coexisting peralkaline melts and high-T brines, they are higher by a factor of 2–3. Zinc continuously increases in hydrothermal fluids (3,000 ppm at 400°C), where the precipitation of sphalerite starts. The main removal of Zn from the fluid system occurs at lower temperatures. Similarly, melt and fluid inclusion concentrations of many other trace elements directly reflect the crystallization and precipitation history of minerals at distinctive temperatures or temperature windows. 相似文献
238.
Kracke D. Heinrich R. Hemmann A. Jentzsch G. Ziegert A. 《Studia Geophysica et Geodaetica》2000,44(4):594-601
The East Thuringian Seismic Network (OTSN) was installed in 1997. It started its operation with five and now consists of six seismic stations, the GRSN (German Regional Seismic Network) station MOX and a control and analysis centre. All stations are equipped with 3-component GÜRALP and short-period seismometers, RefTek 24-bit data acquisition systems (dynamic range 23.5 bit), hard disks, GPS-receivers, modems and communication computers for dial-up purposes. The seismic signals are sampled at 100 Hz and stored on the hard disk. Simultaneously, the signals are processed by a STA/LTA detector which generates an extended event list. The central station calls these event lists once per day, analyses them, produces a list of real seismic events and calls the waveform data for these events only from the single stations. All stations operate completely autonomously and the whole system works automatically, but all operations can also be carried out interactively. The event analysis is performed manually using common seismic analysis programs.
The main purpose of installing the seismic network is to investigate the local seismicity, its relation to recent tectonics, the stress field and structure of the upper crust in order to render more precisely the seismic hazard of East Thuringia. A further aim of the network is to improve the seismic monitoring situation for the neighbouring regions, especially the Vogtland/Northern Bohemia and the Western Saxony area. 相似文献
239.
Prof. Dr. Heinrich Zankl Johannes H. Schroeder Ph. D. 《International Journal of Earth Sciences》1972,61(2):480-483
At the VIII. International Sedimentological Congress held in Heidelberg in 1971, a symposium with the above title was convened; a selection of the papers presented is assembled in this issue. In the introduction the approaches of the following studies are reviewed to show some trends and problems in reef research. 相似文献
240.