全文获取类型
收费全文 | 100篇 |
免费 | 7篇 |
专业分类
测绘学 | 1篇 |
大气科学 | 3篇 |
地球物理 | 22篇 |
地质学 | 17篇 |
海洋学 | 23篇 |
天文学 | 31篇 |
综合类 | 1篇 |
自然地理 | 9篇 |
出版年
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2013年 | 5篇 |
2012年 | 9篇 |
2011年 | 6篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 6篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 6篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有107条查询结果,搜索用时 16 毫秒
41.
Masahiko Tanaka Tomoki Nakamura Takaaki Noguchi Aiko Nakato Hatsumi Ishida Toru Yada Kei Shirai Akio Fujimura Yukihiro Ishibashi Masanao Abe Tatsuaki Okada Munetaka Ueno Toshifumi Mukai 《Meteoritics & planetary science》2014,49(2):237-244
The crystallization temperatures of Itokawa surface particles recovered by the space probe Hayabusa were estimated by a plagioclase geothermometer using sodic plagioclase triclinicity. The Δ131‐index required for the thermometer, which is the difference in X‐ray diffraction peak positions between the 131 and 11 reflections of plagioclase, was obtained by a high‐resolution synchrotron Gandolfi camera developed for the third generation synchrotron radiation beamline, BL15XU at SPring‐8. Crystallization temperatures were successfully determined from the Δ131‐indices for four particles. The observed plagioclase crystallization temperatures were in a range from 655 to 660 °C. The temperatures indicate crystallization temperatures of plagioclases in the process of prograde metamorphism before the peak metamorphic stage. 相似文献
42.
Tae-Soo Pyo Masahiko Hayashi Naoto Kobayashi Alan T. Tokunaga Hiroshi Terada Miwa Goto Takuya Yamashita Yoichi Itoh Hideki Takami Naruhisa Takato Yutaka Hayano Wolfgang Gaessler Yukiko Kamata Yosuke Minowa Masanori Iye 《Astrophysics and Space Science》2003,287(1-4):21-24
We present high angular resolution spectra taken along the jets from L1551 IRS 5 and DG Tau obtained with the Subaru Telescope. The position-velocity diagrams of the [Fe II] λ 1.644 μmemission line revealed remarkably similar characteristics for the two sources, showing two distinct velocity components separated from each other in both velocity and space with the entire emission range blueshifted with respect to the stellar velocity. The high velocity component (HVC) has a velocity of –200 ––300 km s-1 with a narrow line width, while the low velocity component (LVC) is around –100 km s-1 exhibitinig a broad line width. The HVC is located farther away from the origin and is more extended than the LVC. Our results suggest that the HVC is a well-collimated jet originating from the region close to the star, while the LVC is a widely-opened wind accelerated in the region near the inner edge of the accretion disk. 相似文献
43.
Recovery of entire shocked samples in a range of pressure from ~100 GPa to Hugoniot elastic limit 下载免费PDF全文
Keita Nagaki Toshihiko Kadono Tatsuhiro Sakaiya Tadashi Kondo Kosuke Kurosawa Yoichiro Hironaka Keisuke Shigemori Masahiko Arakawa 《Meteoritics & planetary science》2016,51(6):1153-1162
We carried out laser shock experiments and wholly recovered shocked olivine and quartz samples. We investigated the petrographic features based on optical micrographs of sliced samples and found that each recovered sample comprises three regions, I (optically dark), II (opaque), and III (transparent). Scanning electron microscopy combined with electron backscattered diffraction shows that there are no crystal features in the region I; the materials in the region I have once melted. Moreover, numerical calculations performed with the iSALE shock physics code suggest that the boundary between regions II and III corresponds to Hugoniot elastic limit (HEL). Thus, we succeeded in the recovery of the entire shocked samples experienced over a wide range of pressures from HEL (~10 GPa) to melting pressure (~100 GPa) in a hierarchical order. 相似文献
44.
45.
Gatot E. Susilo Koichi Yamamoto Tsuyoshi Imai Yoshiyuki Ishii Hiroshi Fukami Masahiko Sekine 《水文科学杂志》2013,58(3):539-548
Abstract The effect of the El Niño Southern Oscillation (ENSO) on rainfall characteristics in the tropical peatland areas of Central Kalimantan, Indonesia, is demonstrated. This research used rainfall data collected between 1978 and 2008. The results suggest a relationship between ENSO events and the trend in rainfall observed in the study area. Further analyses show that El Niño events have a stronger effect on the rainfall compared to La Niña events. El Niño events were also correlated to the increase in the number of days with less than 1 mm of rainfall in the dry season. The analysis reveals that the impact of El Niño events on rainfall in dry seasons is intensifying annually. Furthermore, ENSO events are not the only factors affecting rainfall trends in the observed area. Other factors, such as deforestation, may also affect the trend. Editor Z.W. Kundzewicz Citation Susilo, G.E., Yamamoto, K., Imai, T., Ishii, Y., Fukami, H., and Sekine, M., 2013. The effect of ENSO on rainfall characteristics in the tropical peatland areas of Central Kalimantan, Indonesia. Hydrological Sciences Journal, 58 (3), 539–548. 相似文献
46.
At the head of Tokyo Bay, coastal upwelling of oxygen-depleted bottom water, induced by northeasterly wind-driven circulation, sometimes leads to the deaths of many shellfish and other aquatic animals across large areas, resulting in substantial economic losses to coastal fisheries. One of the chemical actions associated with this dynamic process is the oxidation of hydrogen sulfide in the bottom water into a colloidal sulfur substance. When sunshine reflects off surface water containing these sulfur particles, the seawater appears milky blue. This phenomenon has been termed “Aoshio.” One of the most important issues to address concerning upwelling in relation to Aoshio is to accurately predict when it will occur as well as its area and scale. In the preliminary study described here, we propose criteria for the occurrence of wind-driven upwelling associated with Aoshio on the southeast shore of Tokyo Bay using two analytical solutions. These two solutions were derived based on some specific assumptions in the context of a two-layered fluid. Comparison with observation data suggested that the criteria were valid. The results of analyses of the sensitivity of the solutions to all of the parameters incorporated into them were also found to be in accord with our qualitative understanding of this phenomenon. 相似文献
47.
The availability of an equation to evaluate the influence of multiple scattering in the single scattering process corresponding
to a layer of arbitrary optical thickness was established. In order to confirm the validity of this equation, the radiance
distribution in this layer was computed using a plane–parallel layer model based on the successive order of scattering method.
The relative errors in a radiance distribution computed were evaluated as a function of optical thickness by the derived equation.
It was shown that this equation provides a theoretical background for determining layer thickness using the plane–parallel
layer model. 相似文献
48.
Multispectral satellite remote sensing can predict shallow-water depth distribution inexpensively and exhaustively, but it requires many in situ measurements for calibration. To extend its feasibility, we improved a recently developed technique, for the first time, to obtain a generalized predictor of depth. We used six WorldView-2 images and obtained a predictor that yielded a 0.648 m root-mean-square error against a dataset with a 5.544 m standard deviation of depth. The predictor can be used with as few as two pixels with known depth per image, or with no depth data, if only relative depth is needed. 相似文献
49.
Impact experiments of inhomogeneous targets such as layered bodies consisting of a dense core and porous mantle were conducted to clarify the effect of the layered structure on impact strength. The layered structure of small bodies could be the result of the thermal evolution of planetesimals in the solar nebula. So, the impact disruption of thermally evolved bodies with core-mantle structure is important for the origin of small bodies such as asteroids. We investigated the impact strength of rocky-layered bodies with porous mantle-sintered cores, which could be formed at an initial stage of thermal evolution. Spherical targets composed of soda-lime glass or quartz core and porous gypsum mantle were prepared as an analog of small bodies with a core-mantle structure, and the internal structure was changed. A nylon projectile was impacted at the impact velocity from 1 to 5 km/s. The impact strength of the core-mantle targets decreases with the increase of the core/target mass ratio (RCM) in the specific energy range from 1×103 to 4×104 J/kg. We observed two distinct destruction modes characterized by the damage to the core: one shows a damaged core and fractured mantle, and the other shows an intact core and broken mantle. The former mode was usually observed with increasing RCM, and the boundary condition of the core destruction () was experimentally found to be , where is the specific energy required to disrupt a glass core. From this empirical equation, it might be possible to discuss the destruction conditions of a thermally evolved body with a porous mantle-sintered core structure. We speculate that the impact strength of the body could be significantly reduced with the progress of internal evolution at the initial stage of thermal evolution. 相似文献
50.
As a new approach to understanding the chondrule formation process, we carried out aerodynamic experiments in which a liquid layer was attached to solid cores, and the breakup of this layer occurred by means of the interaction with a high-velocity gas flow. The size distribution of the dispersed droplets was investigated and compared with the size distributions of chondrules. Both distributions had an exponential form. Using the experimental results, the hydrodynamic pressure to produce the chondrule size distributions was estimated to be ∼ 104 Pa. 相似文献