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11.
Yanjun Shen Taikan Oki Shinjiro Kanae Naota Hanasaki Nobuyuki Utsumi Masashi Kiguchi 《水文科学杂志》2013,58(10):1775-1793
AbstractChanges in water resources availability, as affected by global climate warming, together with changes in water withdrawal, could influence the world water resources stress situation. In this study, we investigate how the world water resources situation will likely change under the Special Report on Emissions Scenarios (SRES) by integrating water withdrawal projections. First, the potential changes in water resources availability are investigated by a multi-model analysis of the ensemble outputs of six general circulation models (GCMs) from organizations worldwide. The analysis suggests that, while climate warming might increase water resources availability to human society, there is a large discrepancy in the size of the water resource depending on the GCM used. Secondly, the changes in water-stressed basins and the number of people living in them are evaluated by two indices at the basin scale. The numbers were projected to increase in the future and possibly to be doubled in the 2050s for the three SRES scenarios A1b, A2 and B1. Finally, the relative impacts of population growth, water use change and climate warming on world water resources are investigated using the global highly water-stressed population as an overall indicator. The results suggest that population and socio-economic development are the major drivers of growing world water resources stress. Even though water availability was projected to increase under different warming scenarios, the reduction of world water stress is very limited. The principal alternative to sustainable governance of world water resources is to improve water-use efficiency globally by effectively reducing net water withdrawal.
Editor Z.W. Kundzewicz; Associate editor D. Gerten 相似文献
12.
Nobuyuki Morikawa Shigeki Senna Yuzuru Hayakawa Hiroyuki Fujiwara 《Pure and Applied Geophysics》2011,168(3-4):645-657
The strong ground motion prediction method ??Recipe?? was published by the Headquarters for Earthquake Research Promotion (HERP) of Japan. HERP has applied this method to prepare shaking maps for scenario earthquakes in specific active faults. Recently, Recipe was updated following its verification by simulations of strong ground motions associated with the Mw?=?6.6 off-shore earthquake west of Fukuoka prefecture in 2005, which occurred in the northwest part of the Kego fault zone located in northern Kyushu, Japan. One of the prominent changes in the upgraded version of Recipe is the inclusion of a procedure to evaluate seismic intensities on the ground surface from waveforms of S-wave velocity of 400?m/s on the engineering bedrock. By applying the upgraded version of Recipe, we have made shaking-maps for earthquakes in the southeast part of the Kego fault zone, which is located directly below the mega-city of Fukuoka. We assume four source models for scenario earthquakes; the locations of the asperities and the hypocenters vary between the models. The results show that in all cases, disastrous seismic intensities can strike a wide area of Fukuoka city. Differences in the distributions of seismic intensities among the four cases can be clearly observed in the area located on the extension of the source fault. Furthermore, we construct a velocity-layer structure model on the engineering bedrock for the central area of Fukuoka city. We assess not only the distribution of seismic intensities but also waveforms on the ground by using an equivalent linear method for the central area of Fukuoka city. 相似文献
13.
Strong motion uncertainty determined from observed records by dense network in Japan 总被引:2,自引:1,他引:1
Nobuyuki Morikawa Tatsuo Kanno Akira Narita Hiroyuki Fujiwara Toshihiko Okumura Yoshimitsu Fukushima Aybars Guerpinar 《Journal of Seismology》2008,12(4):529-546
The variation of ground motions at specific stations from events in six narrow areas was inspected by using K-NET and KiK-net
records. A source-area factor for individual observation stations was calculated by averaging ratios between observed values
for horizontal peak acceleration and velocity, as well as acceleration response spectra for 5% damping, and predicted values
using a ground-motion model (usually known as an attenuation relation) by Kanno et al. (Bull Seismol Soc Am, 96:879–897, 2006). Standard deviations between observed and predicted amplitudes after the correction factor are less than 0.2 on the logarithmic
scale and decrease down to around 0.15 in the short-period range. Intra-event standard deviation clearly increases with decreasing
distance due to differing paths around near source area. Standard deviations may increase with amplitude or decrease with
magnitude; however, both amplitude and magnitude of the data are strongly correlated with distance. The standard deviation
calculated in this study is obviously much smaller than that of the original ground-motion model, as epistemic uncertainties
are minimized by grouping ground motions at specific stations. This result indicates that the accuracy of strong ground motion
prediction could be improved if ground-motion models for specified region are determined individually. For this to be possible,
it is necessary to have dense strong-motion networks in high-seismicity regions, such as K-NET and KiK-net. 相似文献
14.
15.
Keisuke Taira Toshihiko Teramoto Nobuyuki Shikama Kensuke Takeuchi 《Journal of Oceanography》1978,34(2):73-77
An examination of behaviors of a subsurface drogue and a subsequent examination of current measurement with a drifter comprising the drogue as its important part are made in the channel between Oshima and Izu Peninsula. The drogue submerged to the anticipated depth of 300 m within 10 minutes after launching. Since then the drogue kept its depth and operated normally. From the comparison with the velocity measurement by the use of a currentmeter moored at a station in the vicinity of the drifter's track, it is verified that the drifter's motion well reflects the motion of a water parcel around the drogue. 相似文献
16.
A time-series sediment trap was deployed from December 1994 to February 2002 at the mouth of Tokyo Bay (35°03′ N, 139°40′
E; water depth, 850 m). Sinking particles were obtained with a time interval of one week at a depth of approximately 100 m
above the sea floor. Observed total mass fluxes varied from 3.3 to 226.7 g/m2/day with an average of 28.0 g/m2/day. Concentrations of rare earth elements, Al, Ca and Si in particulate materials were measured. The combustible fraction
at 450°C is assumed to be equivalent to the organic matter content. Contents of biogenic materials, namely organic matter,
opal and calcium carbonate, were about 30% and the content of lithogenic material was about 70%. Using La/Yb ratios of particles
from the sediment trap and Tama-gawa River and surface sediment of Tokyo Bay, it was estimated that about 50% of the lithogenic
particles collected in the sediment trap at the mouth of Tokyo Bay originated from resuspended surface sediment in Tokyo Bay.
An increasing trend of Opal/CaCO3 ratio in the sinking particles was found in the spring season. It is suggested that the relative increase of diatoms is due
to the decreasing dissolved inorganic nitrogen input into Tokyo Bay. 相似文献
17.
In order to examine the accumulation pattern of organotin compounds (OTs) accompanying the migration pattern in diadromous fish, tributyltin (TBT) and triphenyltin (TPT) compounds and their derivatives were determined in the liver, muscle, gill, and ovary tissues of both sea-run and freshwater-resident masu salmon, which are of the same species, Oncorhynchus masou. Their migratory histories were estimated using strontium (Sr) and calcium (Ca) analysis in the otolith. A significant difference in the mean Sr:Ca ratio from the core to the edge of the otolith was found between sea-run and freshwater-resident masu salmon. The TBT concentration in the liver was significantly higher than that in the other tissues in both sea-run and freshwater-resident fishes. In sea-run masu salmon, the TBT concentrations in all tissues except for the ovary were significantly higher than in those of freshwater-resident individuals. In the sea-run type, the percentage of TBT was higher than that of the freshwater-resident type. The TPT concentration in the liver of the sea-run type was also significantly higher than that in the other tissues, while that in the gill of the freshwater-resident type was significantly higher than that in the other tissues except for the ovary. The TPT concentrations found in the liver and muscle of the sea-run type were significantly higher than those in the freshwater-resident type, whereas the values of the gill in the sea-run type were significantly lower than those in the freshwater-resident fish examined. The percentage of TPT in the sea-run type was higher than that of the freshwater-resident type. These results suggest that the sea-run O. masou has a higher ecological risk of TBT and TPT exposure than the freshwater-residents during their life history. 相似文献
18.
Kurt Leinenweber Wataru Utsumi Yoshihiko Tsuchida Takehiko Yagi Kei Kurita 《Physics and Chemistry of Minerals》1991,18(4):244-250
New high-pressure orthorhombic (GdFeO3-type) perovskite polymorphs of MnSnO3 and FeTiO3 have been observed using in situ powder X-ray diffraction in a diamond-anvil cell with synchrotron radiation. The materials are produced by the compression of the lithium niobate polymorphs of MnSnO3 and FeTiO3 at room temperature. The lithium niobate to perovskite transition occurs reversibly at 7 GPa in MnSnO3, with a volume change of -1.5%, and at 16 GPa in FeTiO3, with a volume change of -2.8%. Both transitions show hysteresis at room temperature. For MnSnO3 perovskite at 7.35 (8) GPa, the orthorhombic cell parameters are a=5.301 (2) A, b=5.445 (2) Å, c=7.690 (8) Å and V= 221.99 (15) Å3. Volume compression data were collected between 7 and 20 GPa. The bulk modulus calculated from the compression data is 257 (18) GPa in this pressure region. For FeTiO3 perovskite at 18.0 (5) GPa, cell parameters are a=5.022 (6) Å, b=5.169 (5) Å, c=7.239 (9) Å and V= 187.94 (36) Å3. Based on published data on the quench phases, the FeTiO3 perovskite breaks down to a rocksalt + baddelyite mixture of FeO and TiO2 at 23 GPa. This is the first experimental verification of the pressure-induced breakdown of a perovskite to simple oxides. 相似文献
19.
20.
For the purpose of determining the orientation of the OH? dipole in an optically anisotropic crystal, distribution of polarized IR absorbance is formulated under Fourier transform microspectroscopy. The formulatd absorbance distribution suggests that the degree of pleochroism of absorbance depends on the angle between the orientation of the OH? dipole and the principal orientation of the optically anisotropic crystal. As its application, the general orientation of the OH? dipole in topaz is determined to be inclined 27.3° from the c-axis in (010). 相似文献