全文获取类型
收费全文 | 170篇 |
免费 | 3篇 |
国内免费 | 13篇 |
专业分类
测绘学 | 4篇 |
大气科学 | 19篇 |
地球物理 | 40篇 |
地质学 | 46篇 |
海洋学 | 47篇 |
天文学 | 17篇 |
综合类 | 7篇 |
自然地理 | 6篇 |
出版年
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 8篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 4篇 |
2014年 | 4篇 |
2013年 | 13篇 |
2012年 | 3篇 |
2011年 | 12篇 |
2010年 | 6篇 |
2009年 | 4篇 |
2008年 | 19篇 |
2007年 | 13篇 |
2006年 | 11篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 8篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1981年 | 1篇 |
1979年 | 3篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1973年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有186条查询结果,搜索用时 15 毫秒
21.
This paper presents a case study that assessed spatial variations in the tectonic uplift rates of beach deposits in the relict Kujukuri strand plain, situated on the northeastern coast of the Boso Peninsula, eastern Japan. The southern Boso Peninsula is tilted downward to the northeast due to plate subduction along the Sagami Trough. However, the cause of the northeastern coast uplift creating the relict strand plain is unclear, due to the absence of a Holocene raised marine terrace sequence. Elevations and ages of beach deposits were collected from drilled cores and ground-penetrating radar profiles along three shore-normal sections in the southern Kujukuri strand plain. From this, alongshore variations in the relative sea level since the mid-Holocene could be seen. These corresponded to north-to-northeast downward tilting at a rate of 0.4 m/ka for an interval 10 km and are concordant with the longer term tilting of the last interglacial marine terrace surrounding the plain. Although it is difficult to assess shore-normal variations of uplift based on the present dataset, the recognized tilting apparently continues to the tilting of the southern Boso Peninsula, implying the Sagami Trough probably affects the uplift of the Kujukuri coast. 相似文献
22.
23.
24.
T. Murakami 《Astrophysics and Space Science》1995,231(1-2):57-63
ASCA has observed two Soft Gamma-ray burst Repeaters (SGRs) among three known. This is a short report of the two SGRs, 1806–20 and 0526–66(N49). The observed X-ray characteristics favor a spin-powered system for SGR1806-20 and no ASCA detection of the hard X-ray component from SGR0526–66 suggests a very soft spectrum of the ROSAT HRI X-ray point source. 相似文献
25.
Based on calculations of data from FGGE Level III b, a discussion is made of the energy balance in the 40-50 day periodic oscillation over the Asian monsoon region during the 1979 summer. It is found that the main source of 40-50 day periodic perturbation is the monsoon region extending from central South Asia to Southeast Asia. In the upper layer over the North Pacific subtropical area (10-20oN, 150oE-150oW) pres-sure work turns into kinetic energy that maintains 40-50 day periodic perturbation associated with the variation in position and intensity of the mid-Pacific trough. The mean energy budget in the three-dimensional space (0-30oE, 30oE-150oW, 100-1000 hPa) indicates that the 40-50 day periodic perturbation transports kinetic energy to a seasonal mean and a transient perturbation wind field. 相似文献
26.
Probing fault zone heterogeneity on the Nojima fault: Constraints from zircon fission-track analysis of borehole samples 总被引:2,自引:0,他引:2
Fission-track (FT) thermochronologic analysis was performed on zircon separates from rocks in and around the Nojima fault, which was activated during the 1995 Kobe earthquake. Samples were collected from the University Group 500 m (UG-500) borehole and nearby outcrops. FT lengths in zircons from localities > 25 m away from the fault plane as well as one 0.1 m away from the fault in the footwall are characterized by concordant mean values of 10–11 μm and unimodal distributions with negative skewness, which showed no signs of appreciable reduction in FT length. In contrast, those adjacent (< 3 m) to the fault at depths on the hanging wall side showed significantly reduced mean track lengths of 6–8 μm and distributions having a peak around 6–7 μm with rather positive skewness. The former pattern is interpreted to reflect cooling through the zircon partial annealing zone (ZPAZ), without later, partial thermal overprints. The latter indicates substantial track shortening due probably to secondary heating by a thermal event(s) that locally perturbed the geothermal structure. Modeled zircon FT length and age data of partially annealed samples from the UG-500 borehole revealed a cooling episode in the ZPAZ that started at 4 Ma within 3 m from the fault plane, whereas those from the Geological Survey of Japan 750 m borehole record cooling started at 31–38 Ma within 25 m from the fault. On the basis of one-dimensional heat conduction modeling as well as the consistency between the degree of FT annealing and the degree of deformation/alteration of borehole rocks, these cooling ages in both boreholes are interpreted as consequences of ancient thermal overprints by heat transfer or dispersion via fluids in the fault zone. Together with the zircon FT data of a pseudotachylyte layer recently analyzed, it is suggested that the present Nojima fault system was reactivated in the Middle Quaternary from an ancient fault initiated at 56 Ma at mid-crustal depths. Also shown is a temporal/spatial variation in terms of the thermal anomalies recorded in the fault rocks, implying heterogeneity of hot fluid flows in the fault zone. 相似文献
27.
N. Hayashida M. Nagano D. Nishikawa H. Ohoka N. Sakaki M. Sasaki M. Takeda M. Teshima R. Torii T. Yamamoto S. Yoshida K. Honda N. Kawasumi I. Tsushima N. Inoue E. Kusano K. Shinozaki N. Souma K. Kadota F. Kakimoto K. Kamata S. Kawaguchi Y. Kawasaki H. Kitamura Y. Matsubara K. Murakami Y. Uchihori H. Yoshii 《Astroparticle Physics》1999,10(4):125-311
Anisotropy in the arrival directions of cosmic rays with energies above 1017 eV is studied using data from the Akeno 20 km2 array and the Akeno Giant Air Shower Array (AGASA), using a total of about 114 000 showers observed over 11 years. In the first harmonic analysis, we have found a strong anisotropy of 4% around 1018 eV, corresponding to a chance probability of 0.2% after taking the number of independent trials into account. with two-dimensional analysis in right ascension and declination, this anisotropy is interpreted as an excess of showers near the directions of the Galactic Center and the Cygnus region. 相似文献
28.
Masanobu Shimada Hiromi Oaku Yasushi Mitomi Hiroshi Murakami Akira Mukaida Yasuhisa Nakamura Joji Ishizaka Hiroshi Kawamura Tasuku Tanaka Motoaki Kishino Hajime Fukushima 《Journal of Oceanography》1998,54(5):401-416
We present calibration and validation results of the OCTS’s ocean color version-3 product, which mainly consists of the chlorophyll-a concentration (Chl-a) and the normalized water-leaving radiance (nLw). First, OCTS was calibrated for the inter-detector sensitivity difference, offset, and absolute sensitivity using external
calibration source. It was also vicariously calibrated using in-situ measurements for water (Chl-a andnLw) and atmosphere (optical thickness), which were acquired synchronously with OCTS under cloud-free conditions. Second, the
product was validated using selected 17 in-situ Chl-a and 11 in-situnLw measurements. We confirmed that Chl-a was estimated with an accuracy of 68% for Chl-a less than 2 mg/m3, andnLw from 94% (band 2) to 128% (band 4). Geometric accuracy was improved to 1.3 km. Stripes were significantly reduced by modifying
the detector normalization factor as a function of input radiance. 相似文献
29.
Volume transports proceeding to the Kuroshio Extension region and recirculating in the Shikoku Basin 总被引:4,自引:1,他引:3
Akira Nagano Kaoru Ichikawa Hiroshi Ichikawa Masanori Konda Kiyoshi Murakami 《Journal of Oceanography》2013,69(3):285-293
The volume transport of the Kuroshio, the western boundary current of the North Pacific subtropical gyre, varies vigorously due to merging of disturbances propagating from the entire North Pacific. Taking into account the recirculation in the Shikoku Basin by the zonal observation line at 30°N to the west of the Izu–Ogasawara Ridge, we estimated the volume transport in the top 1,000 m layer toward the Kuroshio Extension region. The volume transport of the local recirculation gyre in the Shikoku Basin increases associated with the westward extension of the gyre, particularly in the period of the large meandering path of the Kuroshio south of Japan. Meanwhile, most of the transport variations toward the Kuroshio Extension region correspond to those of the Kuroshio transport on the continental slope south of Japan, which vary independently of those of the recirculation gyre. 相似文献
30.
Large ageostrophic currents in the abyssal layer southeast of Kyushu, Japan, by direct measurement of LADCP 总被引:1,自引:1,他引:0
Akira Nagano Kaoru Ichikawa Hiroshi Ichikawa Yasushi Yoshikawa Kiyoshi Murakami 《Journal of Oceanography》2013,69(2):259-268
With full-depth LADCP velocity data collected in a wide area southeast of Kyushu, Japan, large velocity currents, occasionally exceeding 15 cm s?1, were observed in a thick, 500–1,500 m, near-homogeneous density layer below approximately 3,000 m depth around the steep topographies. The currents were found not to flow along the topographic contours, and to be strongly ageostrophic. The directions of the bottom-layer currents are rather related with phase of the semi-diurnal tides, suggesting deeply intruded internal tides generated at the steep topographies. 相似文献