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311.
Alfred Rittmann 《International Journal of Earth Sciences》1943,33(7-8):485-498
Ohne Zusammenfassung 相似文献
312.
313.
Die Entstehung der Kontinente 总被引:1,自引:0,他引:1
Dr. Alfred Wegener 《International Journal of Earth Sciences》1912,3(4):276-292
Ohne ZusammenfassungDas folgende ist nur ein Auszug aus einer grösseren Arbeit gleichen Titels, die inPetermann's Mitteilungen erscheint. Der wesentliche Inhalt dieser Untersuchungen wurde am 6. Januar 1912 auf der Jahresversammlung der Geologischen Vereinigung in Frankfurt a. M. vorgetragen unter dem Titel: Die Herausbildung der Grossformen der Erdrinde (Kontinente und Ozeane), auf geophysikalischer Grundlage, und weiter am 10. Januar in der Ges. z. Beförd. d. gesamten Naturwiss. zu Marburg unter dem Titel: Horizontalverschiebungen der Kontinente. 相似文献
314.
Kathleen R. Schwindinger Alfred T. Anderson Jr 《Contributions to Mineralogy and Petrology》1989,103(2):187-198
Olivine phenocrysts in the picritic scoria that erupted from Kilauea Iki in 1959 occur as glomeroporphyritic aggregates of 2–16 crystals. The compositions and three-dimensional textures of the olivines vary within an aggregate and within individual lapilli. The attachment of crystals from different environments indicates that these aggregates formed by synneusis — the swimming together of crystals. Most of the crystals are attached along faces with their a crystallographic axes parallel and their c axes either parallel or perpendicular, so that the structural mismatch and interfacial energy are minimized. Observed facial attachments are consistent with fluid dynamical interactions of crystals falling with their large {010} faces horizontal. The aggregates formed in a liquid-rich magma. Rough computations suggest that the minimum aggregation time could be on the order of minutes. Aggregation of very small crystals suggests that the yield strength was less than 3 dynes cm–2. The textures of the aggregates are similar to those of cumulate peridotites. 相似文献
315.
Reliable estimates of minimum spare capacity for world oil production can be obtained by comparing production statistics before and following the collapse of the Iraqi oil industry in March 2003. Spare production was at least 3.2 M b/d (million barrels/day), and was concentrated in the Middle East, mostly in Saudi Arabia (1.7 M b/d), but also in Kuwait and the UAE. This indicates that, assuming Iraqi production returns to its prewar level, a peak in world oil production resulting from resource constraints alone (ignoring political factors) before 2008 can be rejected. This also implies that with an invigorated Iraqi industry, and with further increases in production in the Former Soviet Union and other non-OPEC areas, there would be significant short-term downward pressure on oil prices and strains within OPEC. These transient issues do not alter the projection for a resource-constrained peak or plateau in non-OPEC production between 2010 and 2018. 相似文献
316.
317.
Miroslav Boboň Alfred A. Christy Daniel Kluvanec L’udmila Illášová 《Physics and Chemistry of Minerals》2011,38(10):809-818
Recently, near infrared spectroscopy in combination with double derivative technique has been effectively used by Christy
(Vib Spectrosc 54:42–49, 2010) to study and differentiate between free and hydrogen bonded silanol groups on silica gel surface. The method has given some
insight into the type of functionalities, their location in silica gel samples, and the way the water molecules bind onto
the silanol groups. The important information in this respect comes from the overtones of the OH groups of water molecules
hydrogen-bonded to free silanol groups, and hydrogen-bonded silanol groups absorbing in the region 5,500–5,100 cm−1. Chemically, opal minerals are hydrated silica and the same approach was adapted to study the state of water molecules, silanol
functionalities, and their locations in opal samples from Slovakia. Twenty opal samples classified into CT and A classes and
one quartz sample were used in this work. The samples were crushed using a hydraulic press and powderized. Each sample was
then subjected to evacuation process to remove surface-adsorbed water at 200°C, and the near infrared spectrum of each sample
was measured using a Perkin Elmer NTS FT-NIR spectrometer equipped with a transflectance accessory and a DTGS detector. The
samples were also heated to 750°C to remove the hydrogen-bonded silanol groups on the surface to reveal their locality. Second
derivative profiles of the near infrared reflectance spectra were obtained using the instrument’s software and used in the
detailed analysis of the samples. The analysis of the near infrared spectra and their second derivative profiles had the aim
in finding relationships between the surface chemical structure and the classification of opal samples. The dry opal samples
were also tested for their surface adsorption effectivity toward water molecules. The results indicate that the opal samples
contain (1) surface-adsorbed water, (2) free and hydrogen-bonded silanol groups on the surface, (3) trapped water molecules
in the bulk, and (4) free and hydrogen-bonded silanol groups in the cavity surfaces in the bulk. A part of the water molecules
in the bulk of opal minerals are found as free molecules and the rest are found in hydrogen-bonded state to either free or
vicinal or geminal silanol groups. 相似文献
318.
Muhammad Imran Alfred Stein Raul Zurita-Milla 《International journal of geographical information science》2013,27(2):234-257
Geographical information systems support the application of statistical techniques to map spatially referenced crop data. To do this in the optimal way, errors and uncertainties have to be minimized that are often associated with operations on the data. This paper applies a spatial statistical approach to upscale crop yields from the field level toward the scale of Burkina Faso. Observed yields were related to the Normalized Difference Vegetation Index derived from SPOT-VEGETATION. The objective was to quantify the uncertainties at the subsequent steps. First, we applied a point pattern analysis to examine uncertainties due to the sampling network of field surveys in the country. Second, geographically weighted regression kriging (GWRK) was applied to upscale the yield observations and to quantify the corresponding uncertainty. The proposed method was demonstrated with the mapping of sorghum yields in Burkina Faso and results were compared with those from regression kriging (RK) and kriging with external drift using a local kriging neighborhood (KEDLN). The proposed method was validated with independent yield observations obtained from field surveys. We observed that the lower uncertainty range value increased by 39%, and the upper uncertainty range value decreased by 51%, when comparing GWRK with RK and KEDLN. Moreover, GWRK reduced the prediction error variance as compared to RK (20 vs. 31) and to KEDLN (20 vs. 39). We found that climate and topography had a major impact on the country’s sorghum yields. Further, the financial ability of farmers influenced the crop management and, thus, the sorghum crop yields. We concluded that GWRK effectively utilized information present in the covariate datasets and improved the accuracies of both the regional-scale mapping of sorghum yields and was able to quantify the associated uncertainty. 相似文献
319.
Doug W. Johnson Simon Osborne Robert Wood Karsten Suhre Randy Johnson Steven Businger Patricia K. Quinn Alfred Wiedensohler Philip A. Durkee Lynn M. Russell Meinrat O. Andreae Colin O'Dowd Kevin J. Noone Brian Bandy J. Rudolph Spyros Rapsomanikis 《Tellus. Series B, Chemical and physical meteorology》2000,52(2):290-320
320.