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311.
The L1-SAIF (L1 Submeter-class Augmentation with Integrity Function) signal is one of the Quasi-Zenith Satellite System (QZSS)
navigation signals, which provides an augmentation function for mobile users in Japan. The tropospheric delay correction in
the L1-SAIF augmentation is discussed in detail. Because the topographical features in Japan are complicated, the correction
information is generated from GPS observation data collected at 200 GPS stations which are densely distributed over Japan.
A total of 210 Tropospheric Grid Points (TGPs) are arranged to fully cover Japan. The TGPs that provide the correction information
are selected adaptively to achieve the expected correction accuracy. This selection of TGPs is provided by the TGP mask message.
Mobile users acquire the zenith tropospheric delay (ZTD) value at neighboring TGPs from the correction messages, and can estimate
the local ZTD value accurately by using a suitable ZTD model. Only up to seven L1-SAIF messages are sufficient to provide
the full correction information. Accuracy evaluations have proven that it is possible to achieve a correction accuracy of
13.4 mm RMS. The strategy presented here has been implemented into the augmentation system using the L1-SAIF signal, and its
application guidance is presented in the QZSS interface specification. 相似文献
312.
Satoshi Ishimaru & Kenji Yoshikawa 《Geografiska Annaler: Series A, Physical Geography》2000,82(1):45-57
The weathering of granodiorite porphyry is examined in the extremely cold and dry environment of the inland part of Antarctica. Weathering features include granular disintegration, rock varnish, and sheeting. Sheeting has gradually proceeded since the exposing of the nunatak, but the other types of weathering have not actively advanced in recent times.
Granular disintegration primarily comprises the release of individual crystals. The mechanism of this release is that cracks are created along crystal boundaries and cleavages in phenocrysts mainly due to differential thermal expansion. Plagioclase and hypersthene are released more readily than quartz. Disintegration of plagioclase has produced many prism-shaped holes, 0.5 to 2.0 mm in length, while fine-grained quartz crystals, 0.05 to 0.1 mm in diameter, are incidentally released without cracking.
The reddish brown (10R4/4) rock varnishes result from oxidation and consist of limonite, which fills cracks and penetrates into crystals. Ferrous iron in hypersthene, biotite, ilmenite and magnetite is transformed into limonite by oxidation. Manganese is not found in the varnishes. Sulfur, which is important for oxidation and which may have originated from adhered snow, is concentrated on the surface of the rock.
Sheeting has precipitated rock falls, and has gradually formed a gray mosaic on the varnished wall. The sheeting was caused by gravitational body force, which is internal stress of the rock body due to the mass of the overburden. 相似文献
Granular disintegration primarily comprises the release of individual crystals. The mechanism of this release is that cracks are created along crystal boundaries and cleavages in phenocrysts mainly due to differential thermal expansion. Plagioclase and hypersthene are released more readily than quartz. Disintegration of plagioclase has produced many prism-shaped holes, 0.5 to 2.0 mm in length, while fine-grained quartz crystals, 0.05 to 0.1 mm in diameter, are incidentally released without cracking.
The reddish brown (10R4/4) rock varnishes result from oxidation and consist of limonite, which fills cracks and penetrates into crystals. Ferrous iron in hypersthene, biotite, ilmenite and magnetite is transformed into limonite by oxidation. Manganese is not found in the varnishes. Sulfur, which is important for oxidation and which may have originated from adhered snow, is concentrated on the surface of the rock.
Sheeting has precipitated rock falls, and has gradually formed a gray mosaic on the varnished wall. The sheeting was caused by gravitational body force, which is internal stress of the rock body due to the mass of the overburden. 相似文献
313.
Funakawa Satoshi 《地学前缘》2000,(Z1)
GEOLOGY OF MT. PHULCHOKI AREA, CENTRAL NEPAL 相似文献
314.
315.
The δ18O values of eighteen marine evaporites of Precambrian to Recent ages were found to vary from +8 to 25‰ relative to SMOW, while the δ34S values previously measured by Thode and Monster [2] vary from +10 to +38‰ relative to meteoritic sulfur. The results strongly suggest that the δ18O value of ocean sulfate varied with geologic age with a minimum at the Permian age. 相似文献
316.
Damages resulting from the Tokachi-Oki earthquake of 1968 demonstrated that many code-designed reinforced concrete columns do not have adequate earthquake resistance. A review of Japanese research revealed that the axial force ratio, the moment arm ratio, and the type and ratio of transverse reinforcement control the resistance and ductility of concrete columns. A recent experimental study at the Kajima Institute of Construction Technology evaluated the resistance of columns with three types of transverse reinforcement and three reinforcement ratios subjected to repeated alternating loads. Tied and spiral columns proved to be superior to hooped columns. 相似文献
317.
Forbidden reflections of some pyroxenes described as having a lower symmetry than Pbca or C2/c have been examined, mainly using the detailed ψ-scanning method of the four-circle automated diffractometer. All reflections violating the systematic absences of Pbca orthopyroxene, C2/c spodumene, P2/n omphacite and P21/c pigeonite were found to be due to the Umweganregung process of multiple diffraction; the Umweganregung peaks observed for the ψ azimuth were indexed in terms of a four-circle geometry. Thus, the space groups of orthopyroxene, α spodumene, low omphacite and low pigeonite were confirmed to be Pbca, C2/c, P2/n and P21/c, respectively. 相似文献
318.
Xu Wenjun Zhao Weiming Chai Chizhang Jin Yanlong Sun Lixin Zheng Sihu Satoshi Miura 《中国地震研究》2001,15(3):252-265
INT正ODU**!0厂Nln以la Is located In the nol’th segmentdthe North-southselsnuc Belt,Whlchls thejuncturedthe Qinghai-Xizang(Dbet)block,Alxa block and Odos block.In that region,the tectonic activity。svery strong;。y strong earthquakes occu。d In history,such as the 1739 ingluo M。8.0 earthqu拙eandl920 Halyuan M。8.5 eafthquake,etc.; Merately strongeaFthquakes are still veryactlve atpresent,onlyln the Wuzhong-un斟m area,there have been7 e血hquakes tvlth M。>5.0 to occ… 相似文献
319.
Kenji Kashiwaya Toshio Nakamura Nobuki Takamatsu Hideo Sakai Manabu Nakamura Takayoshi Kawai 《Journal of Paleolimnology》1997,18(3):293-297
Physical and chemical properties of two 100 m sediment cores (BDP-93-1, 93-2) obtained from the Buguldeika saddle of Lake Baikal in the eastern Siberia and a 14C-based age scale for the core show that the core bottom is about 400000 years ago and that the changes in the sedimentological environment of the area during the interval were that comparatively coarse and high C/N ratio sediments accumulated in the lake during interglacial periods, and fine material and low C/N ratio during glacial periods. The tentative age scale suggests that the first excursion in the earth's magnetic field at about 26 m (BDP-93-1 and 93-2) from the sediment surface corresponds to the Blake event. Statistical analyses of the data-sets for the some properties show that the fluctuations have distinct periods; 20000 years, 40000 years and 100000 years, that are related to the Milankovitch parameters and support that the tentative age scale is approximately acceptable. 相似文献
320.
Satoshi Hinata 《Solar physics》1982,80(1):173-183
Current dissipation models of coronal loop heating are studied. Turbulent current dissipation is shown to lead to a time dependent process because of an enormous mass motion induced in the current layer. A stationary heating process involves only ohmic heating, which requires a large current layer. To insure MHD stability, the loop must be composed of many elements with the oppositely directed currents. A stationary current dissipation process induces the plasma motion across the magnetic field into the loop and down the loop with the speeds v
104 cm s–1 and v
104 cm s–1, respectively. The pressure of the loop is also estimated to be proportional to the current density: p/J=6.3 × 10-8dyn/statamp. 相似文献