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141.
Keisuke Ishida Shigeyuki Suzuki Graciano P. Yumul Carla B. Dimalanta 《Gondwana Research》2011,19(1):61-70
The Cabog Formation, newly established herein and exposed in central East Luzon, Philippine Mobile Belt, is defined in age by the occurrence of radiolarians. The radiolarian assemblage is correlative with the middle Eocene and suggests a low paleolatitude affinity. The correlation, sedimentary environment, and the tectonic significance are discussed. The Cabog Formation is correlative with the distal part of the middle–late Eocene Caraballo Formation, which is exposed in the northeastern side of the Philippine Fault Zone. The sandstone composition and radiolarian age suggest that the Cabog Formation represents the first depositional stage in the early arc setting. The northward migration of the formation is also estimated in relation with the Philippine Sea Plate motion along the Older Philippine Fault from the equatorial area. 相似文献
142.
M. Suzuki 《Solar physics》2014,289(11):4021-4029
Long-term modulation of solar differential rotation was studied with data from Mt. Wilson and our original observations during Solar Cycles 16 through 23. The results are that i) the global B-value (i.e. latitudinal gradient of differential rotation) is modulated with a period of about six or seven solar cycles, ii) the B-values of the northern and southern hemispheres are also modulated with a period similar to the global one, but iii) they show quasi-oscillatory behavior with a phase shift between them. We examined the yearly fluctuations of the B-values in every solar cycle with reference to the phase of the sunspot cycle and found that the B-values in the sunspot-minimum years show large and erratic variations, while those in the sunspot-maximum years show small fluctuations. Positive correlation between the former B-values and the latter was found. We discuss the independent long-term behavior of solar differential rotation between the northern and southern solar hemispheres and the implication for the solar dynamo. 相似文献
143.
Akira Tsuchiyama Masayuki Uesugi Kentaro Uesugi Tsukasa Nakano Ryo Noguchi Toru Matsumoto Junya Matsuno Takashi Nagano Yuta Imai Akira Shimada Akihisa Takeuchi Yoshio Suzuki Tomoki Nakamura Takaaki Noguchi Masanao Abe Toru Yada Akio Fujimura 《Meteoritics & planetary science》2014,49(2):172-187
In this study, the three‐dimensional (3‐D) microstructure of 48 Itokawa regolith particles was examined by synchrotron microtomography at SPring‐8 during the preliminary examination of Hayabusa samples. Moreover, the 3‐D microstructure of particles collected from two LL6 chondrites (Ensisheim and Kilabo meteorites) and an LL5 chondrite (Tuxtuac meteorite) was investigated by the same method for comparison. The modal abundances of minerals, especially olivine, bulk density, porosity, and grain size are similar in all samples, including voids and cracks. These results show that the Itokawa particles, which are surface materials from the S‐type asteroid Itokawa, are consistent with the LL chondrite materials in terms of not only elemental and isotopic composition of the minerals but also 3‐D microstructure. However, we could not determine whether the Itokawa particles are purely LL5, LL6, or a mixture of the two. No difference between the particles collected from Rooms A and B of the sample chamber, corresponding to the sampling sequence of the spacecraft's second and first touchdowns, respectively, was detected because of the statistically small amount of particles from Room B. 相似文献
144.
C. Kaito Y. Ojima K. Kamitsuji O. Kido Y. Kimura H. Suzuki T. Sato T. Nakada Y. Saito C. Koike 《Meteoritics & planetary science》2003,38(1):49-57
Abstract— Experimental studies of coalescence between Mg grains and SiO grains in smoke reveal the direct production of crystalline forsterite grains. The present results also show that different materials can be produced by grain‐grain collisions, which have been considered one of the models of grain formation in the interstellar medium. The fundamentals of coalescence growth in smoke, which have been developed in our series of experiments, are presented in this paper. Mg2Si polyhedral grains were obtained in a Mg grain‐rich atmosphere. Mg2SiO4 polyhedral grains were obtained in a SiO grain‐rich atmosphere. The IR spectra of the resultant grains showed the characteristics of crystalline forsterite. 相似文献
145.
ShigeyukiSuzuki AbdulR.Ashraf HakuyuOkada 《东北亚地学研究》2004,7(2):149-155
Sedimentary facies of the Tsagayan Formation is distributed in the eastern Zeya-Bureya Basin has been analyzed. The formation is of the Maastrichtian to Danian in age and characterized by the cyclicity of the fining-upwards successions. Analysis of environmental changes during the K/T boundary is the focus of this study. Five facies have been identified: Facies A, thick and laterally extensive coarse-grained to medium-gained sandstone units, interpreted as channelfill deposits; Facies B, parallel-laminated to massive mudstone units interpreted as interchannel lakes and flood plain deposits; Facies C, sheet-like medium-grained to fine-grained sandstones interpreted as crevasse splay deposits; Facies D, coal to coaly mudstone beds interpreted as deposits of peatlands; Facies E, very poorly sorted sandy mudstone beds interpreted as debris flow deposits. Fluvial environments with the low-relief fiat topography was inferred. A channel transported large volumes of clasts, and a flood basin with interchannel lakes and peatlands was deciphered. Any distinct change of sedimentary environments has not been identified throughout the Tsagayan Formation (including the K/T boundary). However, two beds of debris flow deposits were identified. The one occurs at the uppermost part of the lower Tsagayan Subformation and contains dinosaur fossils. The other is intercalated in the upper Tsagayan Subformation. 相似文献
146.
A. Kawachi Y. Hayami J. Jimbo S. Kamei T. Kifune H. Kubo J. Kushida S. LeBohec K. Miyawaki M. Mori K. Nishijima J. R. Patterson R. Suzuki T. Tanimori S. Yanagita T. Yoshikoshi A. Yuki 《Astroparticle Physics》2001,14(4):1492-269
A new imaging atmospheric Cherenkov telescope with a light-weight reflector has been constructed. Light, robust, and durable mirror facets of containing carbon fiber reinforced plastic laminates were developed for the telescope. The reflector has a parabolic shape (f/1.1) with a 30 m2 surface area, which consists of 60 spherical mirror facets. The image size of each mirror facet is 0°.08 (FWHM) on average. The attitude of each facet can be adjusted by stepping motors. After the first in situ adjustment, a point image of about 0°.14 (FWHM) over 3° field of view was obtained. The effect of gravitational load on the optical system was confirmed to be negligible at the focal plane. The telescope has been in operation with an energy threshold for γ-rays of 300 GeV since May 1999. 相似文献
147.
Sato T. Suzuki Y. Kashiwagi H. Nanjo M. Kakui Y. 《Oceanic Engineering, IEEE Journal of》1978,3(1):1-4
A laser method for the remote detection of oil present as a pollutant in the sea water using Raman backscattering and backscattered fluorescence is discussed. The scattering spectra of oils obtained by using a laser Raman spectrometer that employs a CW Ar laser are described. The backscattering spectra of oils obtained by a laser radar technique in the laboratory and the field are also described. Furthermore, theoretical performance of a laser radar with a CW laser or a pulsed laser for the detection of Raman backscattering of kerosene is discussed. 相似文献
148.
The latest eruption of Haruna volcano at Futatsudake took placein the middle of the sixth century, starting with a Plinianfall, followed by pyroclastic flows, and ending with lava domeformation. Gray pumices found in the first Plinian phase (lowerfall) and the dome lavas are the products of mixing betweenfelsic (andesitic) magma having 50 vol. % phenocrysts and maficmagma. The mafic magma was aphyric in the initial phase, whereasit was relatively phyric during the final phase. The aphyricmagma is chemically equivalent to the melt part of the phyricmafic magma and probably resulted from the separation of phenocrystsat their storage depth of 15 km. The major part of the felsicmagma erupted as white pumice, without mixing and heating priorto the eruption, after the mixed magma (gray pumice) and heatedfelsic magma (white pumice) of the lower fall deposit. Althoughthe mafic magma was injected into the felsic magma reservoir(at 7 km depth), part of the product (lower fall ejecta) precedederuption of the felsic reservoir magma, as a consequence ofupward dragging by the convecting reservoir of felsic magma.The mafic magma injection made the nearly rigid felsic magmaerupt, letting low-viscosity mixed and heated magmas open theconduit and vent. Indeed the lower fall white pumices preservea record of syneruptive slow ascent of magma to 2 km depth,probably associated with conduit formation. KEY WORDS: high-crystallinity felsic magma; magma plumbing system; multistage magma mixing; upward dragging of injected magma; vent opening by low-viscosity magma 相似文献
149.
Konstantin D. Litasov Eiji Ohtani Akio Suzuki Kenichi Funakoshi 《Physics and Chemistry of Minerals》2007,34(3):159-167
High-pressure in situ X-ray diffraction experiment of Fe- and Al-bearing phase D (Mg0.89Fe0.14Al0.25Si1.56H2.93O6) has been carried out to 30.5 GPa at room temperature using multianvil apparatus. Fitting a third-order Birch–Murnaghan equation of state to the P–V data yields values of V 0 = 86.10 ± 0.05 Å3; K 0 = 136.5 ± 3.3 GPa and K′ = 6.32 ± 0.30. If K′ is fixed at 4.0 K 0 = 157.0 ± 0.7 GPa, which is 6% smaller than Fe–Al free phase D reported previously. Analysis of axial compressibilities reveals that the c-axis is almost twice as compressible (K c = 93.6 ± 1.1 GPa) as the a-axis (K a = 173.8 ± 2.2 GPa). Above 25 GPa the c/a ratio becomes pressure independent. No compressibility anomalies related to the structural transitions of H-atoms were observed in the pressure range to 30 GPa. The density reduction of hydrated subducting slab would be significant if the modal amount of phase D exceeds 10%. 相似文献
150.
Twenty four solar bursts of peak fluxes above 50 sfu are analyzed which were observed with the 17 GHz interferometer at Nobeyama during the period from 1978 September to 1979 December. Source characteristics and their temporal evolutions are investigated on a statistical basis with high time resolutions up to 0.8 s. Use of a model-fitting technique recently developed by Kosugi (1982) is made to derive both the position of centroid and size (~ FWHM) of burst source with an uncertainty of a few arc sec. The results of this study are the following:
- Two different phases in the burst, that is to say, the main phase and the post-burst-increase (PBI) phase, are distinguished clearly not only by the morphological difference of flux time profile, but also by the differences of brightness temperature (107-?109 K vs 105–107 K), circular polarization degree (0–50% vs 0–10%), and size (?5–25″ vs 10–70″). There is no definite correlation between the peak fluxes in the two phases.
- The majority of the selected bursts (21 of 24) show in the main phase source characteristics of the impulsive burst. The total flux varies rapidly (characteristic time scale defined by FWHM ? 100 s), often associated with the rapid shift of position and the rapid change of polarization degree. The source height of the impulsive source is lower than that of the PBI source. On the other hand, the type IVμ source, seen in three events, shows a gradual variation and the source ascends to a height of ~ 40 000 km above the photosphere.
- In the PBI phase, the expansion and ascension of the source occur in general (21 of 23 for the former and 12 of 15 for the latter). The velocities of both the movements are of the order of 5 km s?1.