全文获取类型
收费全文 | 179篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
大气科学 | 7篇 |
地球物理 | 45篇 |
地质学 | 37篇 |
海洋学 | 56篇 |
天文学 | 28篇 |
综合类 | 1篇 |
自然地理 | 10篇 |
出版年
2024年 | 1篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 9篇 |
2015年 | 2篇 |
2014年 | 7篇 |
2013年 | 7篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 14篇 |
2009年 | 14篇 |
2008年 | 15篇 |
2007年 | 12篇 |
2006年 | 11篇 |
2005年 | 7篇 |
2004年 | 2篇 |
2003年 | 8篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 8篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有184条查询结果,搜索用时 31 毫秒
141.
Hideharu Sasaki Shang-Ping Xie Bunmei Taguchi Masami Nonaka Shigeki Hosoda Yukio Masumoto 《Journal of Oceanography》2012,68(1):93-111
Interannual variations of the Hawaiian Lee Countercurrent (HLCC) in the 2000s were investigated using satellite and Argo profiling
float observations. The satellite-observed sea surface height shows that the geostrophic eastward current was anomalously
strong to the west away from Hawaii in 2003 and 2005. However, the trade winds and the orographic wind curl dipole in the
lee of Hawaii that drives the climatological mean HLCC were not particularly strong in these years, suggesting that the accelerations
of the HLCC were not caused by the wind stress curl forcing around Hawaii and subsequent Rossby wave propagation. Using Argo
observations, we found negative potential vorticity (PV) anomalies in the subsurface north of the HLCC in these 2 years. The
pycnocline is lifted northward as low PV waters of different densities stack up in the vertical, and the HLCC is then accelerated
via the thermal wind. The intensification and/or southward intrusion of the eastern subtropical mode water and subtropical
mode water seem to have induced negative PV anomalies in 2003 and 2005, respectively. Using high-resolution ocean simulations,
we confirmed the migrations of PV anomalies and their contributions to the HLCC accelerations. Although the HLCC is located
away from the cores of major mode waters, our results suggest that interannual variations of the HLCC are affected by those
of mode waters. 相似文献
142.
Effects of mesoscale eddies on the marine ecosystem in the Kuroshio Extension (KE) region are investigated using an eddy-resolving
coupled physical-biological model. The model captures the seasonal and intra-seasonal variability of chlorophyll distribution
associated with the mesoscale eddies, front variability, Kuroshio meanders, and upwelling. The model also reproduces the observed
interannual variability of sea surface height anomaly (SSHA) in the KE region along a zonal band of 32–34°N from 2002 to 2006.
The distribution of high surface chlorophyll corresponds to low SSHA. Cyclonic eddies are found to detach from the KE jet
near 150°E and 158°E and propagate westward. The westward propagating cyclonic eddies lift the nutrient-rich thermocline into
the euphotic zone and maintain high levels of chlorophyll in summer. In the subsurface layer, the pattern in chlorophyll is
influenced by both lateral and vertical advection. In winter, convection inside the eddy entrains high levels of nutrients
into the mixed layer, increasing production, and resulting in high chlorophyll concentration throughout the surface mixed
layer. There is significant interannual variability in both the cyclonic eddy activity and the surface phytoplankton bloom
south of the KE jet, although whether or not there is a causal link is unclear. 相似文献
143.
Takuya Hasegawa Kentaro Ando Keisuke Mizuno Roger Lukas Bunmei Taguchi Hideharu Sasaki 《Ocean Dynamics》2010,60(5):1255-1269
We investigate the relationship between sea surface temperature (SST) cooling and upwelling along Papua New Guinea’s (PNG) north coast before the onset of El Niño events using a hindcast experiment with a high-resolution ocean general circulation model. Coastal upwelling and related SST cooling appear along PNG north coast during the boreal winter before the onsets of six El Niño events occurring during 1981–2005. Relatively cool SSTs appear along PNG north coast during that time, when anomalous northwesterly surface wind stress, which can cause coastal upwelling by offshore Ekman transport appearing over the region. In addition, anomalous cooling tendencies of SST are observed, accompanying anomalous upward velocities at the base of the mixed layer and shallow anomalies of 27°C isotherm depth. It is also shown that entrainment cooling plays an important role in the cooling of the mixed layer temperature in this region. 相似文献
144.
Bunmei Taguchi Bo Qiu Masami Nonaka Hideharu Sasaki Shang-Ping Xie Niklas Schneider 《Ocean Dynamics》2010,60(3):673-691
An eddy-resolving multidecadal ocean model hindcast simulation is analyzed to investigate time-varying signals of the two recirculation gyres present respectively to the north and south of the Kuroshio Extension (KE) jet. The northern recirculation gyre (NRG), which has been detected at middepth recently by profiling float and moored current meter observations, is a major focus of the present study. Low-frequency variations in the intensity of the recirculation gyres are overall highly correlated with decadal variations of the KE jet induced by the basin-wide wind change. Modulation of the simulated mesoscale eddies and its relationship with the time-varying recirculation gyres are also evaluated. The simulated eddy kinetic energy in the upstream KE region is inversely correlated with the intensity of the NRG, consistent with previous observational studies. Eddy influence on the low-frequency modulation of the NRG intensity at middepth is further examined by a composite analysis of turbulent Sverdrup balance, assuming a potential vorticity balance between the mean advection and the convergent eddy fluxes during the different states of the recirculation gyre. The change in the NRG intensity is adequately explained by that inferred by the turbulent Sverdrup balance, suggesting that the eddy feedback triggers the low-frequency modulation of the NRG intensity at middepth. 相似文献
145.
Charles W. Mandeville Akira Sasaki Genji Saito Kevin Faure Robert King Erik Hauri 《Earth and Planetary Science Letters》1998,160(3-4):709-722
We present the first sulfur and oxygen isotopic data for tephra from the catastrophic 1883 eruption of Krakatau. Sulfur isotopic ratios in unaltered Krakatau tephra erupted August 26–27, 1883 are markedly enriched in 34S relative to mantle sulfur. High δ34S values of +6.3 to +16.4‰ can best be explained by open-system or multi-stage degassing of SO2 from the oxidized rhyodacitic and gray dacitic magmas with 34S enrichment of SO2−4 remaining in the melt. Lower whole-rock δ34S values of +2.6‰ and +4.0‰ in two oxidized gray dacitic samples indicate more primitive subarc mantle sulfur in the 1883 magma chamber. Initial δ34S of the rhyodacitic magma was probably in the +1.5‰ to +4.0‰ range and similar to δ34S values measured in arc volcanic rocks from the Mariana Arc. 相似文献
146.
Does heavy oil pollution induce bacterial diseases in Japanese flounder Paralichthys olivaceus? 总被引:1,自引:1,他引:0
Jun-Young Song Kei Nakayama Yasunori Murakami Sung-Ju Jung Myung-Joo Oh Satoru Matsuoka Hidemasa Kawakami Shin-Ichi Kitamura 《Marine pollution bulletin》2008,57(6-12):889
As basic research for the effect of heavy oil on the fish immune system, in this study, the number of leukocyte was counted in Japanese flounder Paralichthys olivaceus, after exposure to heavy oil at a concentration of 30 g/8 L for 3 days. To compare the numbers of bacteria in the skin mucus between oil-exposed and control fish, viable bacteria were enumerated by counting colony forming unit (CFU). Compared with 5.79 ± 1.88 × 107 leukocytes/mL in the controls, the exposed fish demonstrated higher counts, averaging 1.45 ± 0.45 × 108 cells/mL. The bacterial numbers of control fish were 4.27 ± 3.68 × 104 CFU/g, whereas they were 4.58 ± 1.63 × 105 CFU/g in the exposed fish. The results suggest that immune suppression of the fish occurred due to heavy oil stressor, and bacteria could invade in the mucus, resulting in the increasing leukocyte number to prevent infectious disease. 相似文献
147.
Toxicogenomic analysis of immune system-related genes in Japanese flounder (Paralichthys olivaceus) exposed to heavy oil 总被引:1,自引:1,他引:0
Kei Nakayama Shin-Ichi Kitamura Yasunori Murakami Jun-Young Song Sung-Ju Jung Myung-Joo Oh Hisato Iwata Shinsuke Tanabe 《Marine pollution bulletin》2008,57(6-12):445
Heavy oil contamination is one of the most important environmental issues. Toxicities of polycyclic aromatic hydrocarbons (PAHs), including immune toxicities, are well characterized, however, the immune toxic effects of heavy oil, as a complex mixture of PAHs, have not been investigated. In the present study, we selected Japanese flounder (Paralichthys olivaceus) as a model organism, and observed alteration of immune function by the exposure to heavy oil. To analyze the expression profiles of immune system-related genes, we selected 309 cDNAs from our flounder EST library, and spotted them on a glass slide. Using this cDNA array, alteration of gene expression profiles was analyzed in the kidneys of flounders exposed to heavy oil. Six Japanese flounders (mean body weight: 197 g) were acclimated to laboratory conditions at 19–20 °C. Three fish were exposed to heavy oil C (bunker C) at a concentration of 3.8 g/L for 3 days, and the others were kept in seawater without heavy oil and used as the control. After the exposure period, the fish were transferred into control seawater and maintained for 4 days, and then they were dissected and their kidneys were removed. Total RNA was extracted from the kidney samples to use in gene expression analyses. The microarray detected alteration of immune system-related genes in the kidneys of heavy oil-exposed flounders, including down-regulation of immunoglobulin light chain, CD45, major histocompatibility complex class II antigens and macrophage colony-stimulating factor precursor, and up-regulation of interleukin-8 and lysozyme. These results suggest that pathogen resistance may be weakened in heavy oil-exposed fish, causing a subsequent bacterial infection, and then proinflammatory genes may be induced as a defensive response against the infection. Additionally, we found candidate genes for use as biomarkers of heavy oil exposure, such as N-myc downstream regulated gene 1 and heat shock cognate 71 kDa proteins. 相似文献
148.
The annual transport of anthropogenic carbon (Canth) to the North Pacific Intermediate Water (NPIW) from the Western Subarctic Gyre (WSG) has been re-estimated by using newly
estimated Oyashio transport and Canth concentration, the latter calculated by the recently-established “ΔC*” method with some modifications. Estimated annual Canth transport through the nearshore Oyashio west of 146°E was 0.020 ± 0.010 GtC y−1, closely approximating the previous estimation based on a 1-D model calibrated with the CFC vertical distribution. The present
study, however, found that an additional 0.025 ± 0.010 GtC y−1 of Canth was transported into NPIW in the region east of 146°E. Total Canth transport, 0.045 GtC y−1, contributes about 35% of annual Canth accumulation of the whole temperate North Pacific.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
149.
150.
Keiko Sasaki Yoshitaka Uejima Atsushi Sakamoto Qianqian Yu Junichiro Ishibashi Naoko Okibe Tsuyoshi Hirajima 《Resource Geology》2013,63(2):155-165
Microbiological contribution to the formation of the manganese deposits in Sambe hot springs, Shimane, was investigated in combination with water chemistry, characterization of sediments and microbial community structure. Analysis of bacterial and fungal community structure based on DNA extracted from a Mn‐oxidizing enrichment culture indicated close matches with Pseudomonas putida, Phoma sp. and Plectosphaerella cucumerina, all Mn‐oxidizing microorganisms. These sediments were poorly crystalline and formed at neutral pH values, which is characteristic of biogenic precipitates. The EPMA results demonstrated a positive correlation between Mn and Ba contents in well‐crystalline Mn oxide grains. Substantial Ba contents were observed inside Mn oxide grains. These findings indicated that Ba contents in sediments are influenced by not only aqueous Ba2+ concentrations but also crystallinity of biogenic birnessite. Barium would be incorporated in birnessite during biomineralization. 相似文献