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71.
Max Nielsen-Pincus Patricia Sussman Drew E. Bennett Hannah Gosnell Robert Parker 《社会与自然资源》2017,30(12):1423-1441
Sense of place, including an individual’s attitudes toward specific geographic settings, is generally predicted to influence willingness to engage in place-protective behaviors. Relatively little research, however, has empirically examined the influence of people’s attitudes toward a place on their willingness to pay for environmental protection. Using the example of a payment for ecosystem services (PES) initiative in the McKenzie River watershed, Oregon, USA, we found that place attitudes were a significant predictor of respondents’ willingness to pay for a program designed to benefit drinking water quality. These results suggest that connecting conservation actions to landscapes that are meaningful to people may increase their financial support for PES and other conservation programs. While program managers have little or no influence over stakeholders’ political ideology, gender, or income, managers may be able to influence prospective PES buyers’ awareness and attitudes through targeted communications, thereby potentially increasing support for place-based conservation efforts. 相似文献
72.
Landowner Attitudes Toward Conservation Easements: Balancing the Private and Public Interest in Land
Private land conservation provides an opportunity to address problems of habitat fragmentation and biodiversity loss caused by an increase in the development and parcelization of private land. Conservation easements (CEs) are used to protect significant natural qualities of private land. In this study, we explore landowner attitudes toward CEs through the implementation of a mixed-mode survey to private landowners in the Whychus Creek Watershed (Deschutes County, Oregon). The results of an exploratory factor analysis suggest there are two dimensions to landowner attitudes toward CEs, an internal dimension and an external dimension. We found that positive external attitudes are primarily influenced by environmental beliefs, whereas positive internal attitudes are influenced by a suite of factors, including financial beliefs and perceived risk to private ownership. Awareness of CEs may also play a role in attitude development. Through this research, we argue that CEs may be beneficial in reintegrating the public good into private property. 相似文献
73.
Prof. Dr. Max Müller 《Pure and Applied Geophysics》1950,17(1-2):54-63
Zusammenfassung Es wird eine Induktionsimpulsmethode beschrieben, welche sich auf die Messung dielektrischer Dispersionsphänomene gründet, und welche einen direkten Nachweis des Petroleums auf Tiefen von über 2000 m ermöglicht. Durch Variation der Anfachungsbedingungen kann man selektive Reaktionswirkungen erzielen.
Summary An induction pulse method is described, based upon the measurement of a dielectric dispersion phenomenon. This method opens the possibility of a direct and selective reaction of the petroleum at a depth of more than 6000 feet. Hereby the selective reaction is based upon the variation of the exciting conditions.相似文献
74.
Summary Data are given of the vertical distribution of temperature, conductivity and alkalinity of an eutrophic lake (Rotsee near
Lucerne) measured at short intervals during the summer stratification. We were able to prove in a limited measure only the
expected day's periodicity from the conductivity of the CO2-assimilation of the phytoplankton. We found pronounced internal ‘seiches’ in the hypolimnion; their mathematical interpretation
is given only in the order of size.Rodhe's diagram andNümann's method make it possible to determine quantitative relations; from the chemical point of view the lake (depth 16,5 m) shows
a four-layered type during the summer.
相似文献
75.
Max Richter 《International Journal of Earth Sciences》1941,32(1-2):93-105
Ohne Zusammenfassung 相似文献
76.
Max Richter 《International Journal of Earth Sciences》1937,28(1-2):135-136
Ohne Zusammenfassung 相似文献
77.
Max Semper 《International Journal of Earth Sciences》1911,2(5-6):263-277
Ohne Zusammenfassung 相似文献
78.
The dependence of the partitioning of iron and europium between plagioclase and hydrous tonalitic melt on oxygen fugacity 总被引:1,自引:0,他引:1
The dependence of iron and europium partitioning between plagioclase and melt on oxygen fugacity was studied in the system
SiO2(Qz)—NaAlSi3O8(Ab)—CaAl2Si2O8(An)—H2O. Experiments were performed at 500 MPa and 850 °C/750 °C under water saturated conditions. The oxygen fugacity was varied
in the log f
O2-range from −7.27 to −15.78. To work at the most reducing conditions the classical double-capsule technique was modified.
The sample and a C—O—H bearing sensor capsule were placed next to each other within a BN jacket to minimise loss of hydrogen
to the vessel atmosphere. By this setup redox conditions slightly more reducing than the FeO—Fe3O4 buffer could be maintained even in 96 h runs. Raman spectra showed that the BN was modified by reaction with hydrogen resulting
in a low hydrogen permeability. The partition coefficients determined for Eu at 850 °C and 500 MPa vary from 0.095 at conditions
of the Cu—Cu2O buffer to 1.81 at the most reducing conditions (C—O—H sensor). In the same f
O2 interval the partition coefficient for Fe varies from 0.55 at oxidising conditions to 0.08 at the most reducing conditions.
The partitioning of Sm, which was added as a reference for a trivalent REE, does not vary with the oxygen fugacity, yielding
an average value for D = 0.07. Lowering the temperature to 750 °C for a given f
O2 decreases the partition coefficient of Eu and increases that of Fe. Comparison with published data at 1 atm and at higher
temperatures shows that both temperature and composition of the melt have strong effects on the partitioning behaviour. As
the change of the partition coefficients in the geologically relevant f
O2 range is quite strong, element partitioning of Eu and Fe might be used to estimate redox conditions for the genesis of igneous
rocks. Furthermore, by modelling the partitioning data it is possible to extract information about the redox state of the
melt. Resulting ferric-ferrous ratios show significant differences from those predicted by empirical models.
Received: 14 October 1998 / Received: 5 March 1999 相似文献
79.
To facilitate precise and cost-effective watershed management, a simple yet spatially and temporally distributed hydrological model (DHM-WM) was developed. The DHM-WM is based on the Mishra-Singh version of the curve number method, with several modifications: The spatial distribution of soil moisture was considered in moisture updating; the travel time of surface runoff was calculated on a grid cell basis for routing; a simple tile flow module was included as an option. The DHM-WM was tested on a tile-drained agricultural watershed in Indiana, USA. The model with the tile flow module performed well in the study area, providing a balanced water budget and reasonable flow partitioning. The daily coefficient of determination and Nash-Sutcliffe coefficient were 0.58 and 0.56, for the calibration period, and 0.63 and 0.62 for the validation period. The DHM-WM also provides detailed information about the source areas of flow components, the travel time and pathways of surface runoff.
EDITOR A. Castellarin; ASSOCIATE EDITOR F.-J. Chang 相似文献
80.
The origin of an apparently syndeformational chemical remanent magnetization (CRM) and geochemical alteration in a fault zone in the Bristol Channel Basin, southwest England, was investigated. Deformation in the fault zone occurs in Jurassic aged, organic-rich limestones and consists of numerous normal and oblique-slip faults and associated folds. Migration of basinal, radiogenic fluids is indicated by elevated 87Sr/86Sr values for calcite veins that occur throughout the fault zone. Some of the calcite veins contain hydrocarbons sourced from deeper strata. Elevated 87Sr/86Sr values in the host Jurassic limestones indicate that they were also extensively altered by radiogenic fluids that migrated through microfractures in addition to major fault and fracture planes. Folded and tilted host limestones contain a pervasive secondary CRM residing in magnetite that was acquired during deformation in the Tertiary. The association between this pervasive CRM and the pervasive geochemical alteration is consistent with a genetic connection between the orogenic fluids and the CRM although the timing of CRM acquisition (Tertiary) is not consistent with structural interpretations for the timing of most veining. An alternative remagnetization mechanism which is not triggered by externally derived fluids, such as diagenesis of hydrocarbons, might account for the CRM. Hydrocarbon-bearing veins also contain a CRM that resides in magnetite, although the time for remanence acquisition is not well constrained by field tests. © 1998 John Wiley & Sons, Ltd. 相似文献