全文获取类型
收费全文 | 144篇 |
免费 | 8篇 |
国内免费 | 2篇 |
专业分类
测绘学 | 3篇 |
大气科学 | 7篇 |
地球物理 | 38篇 |
地质学 | 45篇 |
海洋学 | 32篇 |
天文学 | 25篇 |
综合类 | 1篇 |
自然地理 | 3篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 9篇 |
2017年 | 3篇 |
2016年 | 8篇 |
2015年 | 12篇 |
2014年 | 10篇 |
2013年 | 9篇 |
2012年 | 7篇 |
2011年 | 11篇 |
2010年 | 10篇 |
2009年 | 12篇 |
2008年 | 9篇 |
2007年 | 2篇 |
2006年 | 7篇 |
2005年 | 7篇 |
2004年 | 11篇 |
2003年 | 6篇 |
2002年 | 3篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有154条查询结果,搜索用时 312 毫秒
101.
H. M. Zakir Hossain Quazi Hasna Hossain Atsushi Kamei Daisuke Araoka 《Arabian Journal of Geosciences》2018,11(23):749
The modal and chemical composition of sands from Cox’s Bazar beach (CBB) and Kuakata beach (KB) areas of Bangladesh has been investigated to infer their maturity, chemical weathering, and provenance signatures. The CBB and KB sands are typically high quartz, low feldspar, and lithic fragments, representing a recycled orogen source. Major element compositions of CBB sands are characterized by high SiO2 (83.52–89.84 wt%) and low Al2O3 (4.39–6.39 wt%), whereas KB sands contained relatively low SiO2 (63.28–79.14 wt%) and high Al2O3 (9.00–11.33 wt%) contents. The major, trace and rare earth element (REE) compositions of beach sands display comparable distribution patterns with enriched Th and SiO2 for both sands relative to upper continental crust (UCC). Pb, Rb, Y, and Fe for KB sands are little higher than UCC and the rest of the elements are marked depleted for both suites reflecting destruction of plagioclase and K-feldspar during fluvial transportation. The CBB and KB sands are compositionally low mature to immature in nature subsequently classified as subarkose and litharenite, respectively. Chondrite-normalized REE patterns for CBB and KB sands show LREE enrichment and nearly flat HREE (LaN/YbN, 7.64–9.38 and 5.48–8.82, respectively) coupled with prominent Eu anomalies (Eu/Eu*, 0.51–0.72 and 0.52–0.76, respectively), suggesting felsic source provenance. The provenance discrimination diagrams, immobile trace element ratios (Th/Sc, Zr/Sc, Ce/Sc, and Ti/Zr), and REE (∑LREE/HREE, Eu/Eu* and GdN/YbN) parameters indicate that CBB and KB sands were largely derived from felsic source rocks, with compositions close to average rhyolite, granodiorite, granite, and UCC. 相似文献
102.
Ching-Ying Tsou Masahiro Chigira Daisuke Higaki Go Sato Hiroshi Yagi Hiroshi P. Sato Akihiko Wakai Vishnu Dangol Shanmukhesh C. Amatya Akiyo Yatagai 《Landslides》2018,15(5):953-965
The devastating Gorkha earthquake (M w 7.8) on April 25, 2015 and its aftershocks triggered numerous landslides across the Lesser and Higher Himalayas of central Nepal. This study aims to characterize these landslides, based on the local topography and geology, and to develop data for landslide hazard zoning. This study focused on a mountainous catchment of the Trishuli River, where a digital elevation model was used to examine hilllslope and river profiles, aerial photos were used to identify 155 coherent landslides, and satellite images were used to map 912 earthquake-induced landslides. The topography of this area is mainly characterized by incised V-shaped inner gorges and steep (> 35°) SW-facing scarp slopes. Although most of the coherent landslides were not reactivated by the earthquakes, the Gogane landslide was affected by the earthquake and partly failed. A majority of the earthquake-induced landslides (91%) were new landslides, while the others were enlarged old landslides. The earthquake-induced landslides occurred mainly on the steep slopes of V-shaped inner gorges and scarp slopes, in gneiss and quartzite strata of the Lesser Himalayas, and they were primarily associated with fractured rock masses. This analysis provides a framework for zoning areas vulnerable to earthquake-induced landslides. 相似文献
103.
104.
Daisuke Inazu Tadahiro Sato Satoshi Miura Yusaku Ohta Kazuyuki Nakamura Hiromi Fujimoto Christopher F. Larsen Tomoyuki Higuchi 《Journal of Oceanography》2009,65(3):335-347
An accurate prediction of ocean tides in southeast Alaska is developed using a regional, barotropic ocean model with a finite
difference scheme. The model skill is verified by the observational tidal harmonics in southeast Alaska including Glacier
Bay. The result is particularly improved in Glacier Bay compared to the previous model described by Foreman et al. (2000). The model bathymetry dominates the model skill. We re-estimate tidal energy dissipation in the Alaska Panhandle
and suggest a value for tidal energy dissipation of 3.4 GW associated with the M2 constituent which is 1.5 times the estimation of Foreman et al. (2000). A large portion of the M2 energy budget entering through Chatham Strait is dissipated in the vicinity of Glacier Bay. Moreover, it is shown that the
developed model has the potential to correct the ocean tide loading effect in geodetic data more efficiently than the model
of Foreman et al. (2000), especially around Glacier Bay. 相似文献
105.
Water mass variability in the western North Pacific detected in a 15-year eddy resolving ocean reanalysis 总被引:2,自引:0,他引:2
106.
107.
Daisuke NAKASHIMA Takayuki USHIKUBO Michael E. ZOLENSKY Noriko T. KITA 《Meteoritics & planetary science》2012,47(2):197-208
Abstract– Oxygen three‐isotope ratios of three anhydrous chondritic interplanetary dust particles (IDPs) were analyzed using an ion microprobe with a 2 μm small beam. The three anhydrous IDPs show Δ17O values ranging from ?5‰ to +1‰, which overlap with those of ferromagnesian silicate particles from comet Wild 2 and anhydrous porous IDPs. For the first time, internal oxygen isotope heterogeneity was resolved in two IDPs at the level of a few per mil in Δ17O values. Anhydrous IDPs are loose aggregates of fine‐grained silicates (≤3 μm in this study), with only a few coarse‐grained silicates (2–20 μm in this study). On the other hand, Wild 2 particles analyzed so far show relatively coarse‐grained (≥ few μm) igneous textures. If anhydrous IDPs represent fine‐grained particles from comets, the similar Δ17O values between anhydrous IDPs and Wild 2 particles may imply that oxygen isotope ratios in cometary crystalline silicates are similar, independent of crystal sizes and their textures. The range of Δ17O values of the three anhydrous IDPs overlaps also with that of chondrules in carbonaceous chondrites, suggesting a genetic link between cometary dust particles (Wild 2 particles and most anhydrous IDPs) and carbonaceous chondrite chondrules. 相似文献
108.
Contamination by organochlorine compounds in sturgeons from Caspian Sea during 2001 and 2002 总被引:2,自引:0,他引:2
Kajiwara N Ueno D Monirith I Tanabe S Pourkazemi M Aubrey DG 《Marine pollution bulletin》2003,46(6):741-747
Organochlorine compounds (OCs) were determined in the five species of sturgeons collected from coastal waters of Caspian Sea in Kazakhstan, Azerbaijan, Turkmenistan and Iran during 2001 and 2002 to understand their status of contamination and accumulation features. Among OCs examined, concentrations of DDTs (DDT and its metabolites) were predominant in all the sturgeon samples with concentrations ranging from 73 to 31,000 ng/g on lipid weight basis, followed by PCBs, CHLs, HCHs, HCB, dieldrin, TCPMOH, and heptachlor epoxide in order. The concentrations of OCs in beluga (Huso huso) were the highest among all the five species. When comparing residue levels among same species, OC residues were highest in sturgeons from Azerbaijan and Kazakhstan and lowest in Turkmenistan. However, the concentrations of HCHs, dieldrin, and heptachlor epoxide in sturgeons showed less geographical variability. 相似文献
109.
Concentrations of persistent organochlorines (OCs) such as PCBs, DDTs, chlordanes (CHLs), HCHs and HCB were determined in the liver of bluefin tuna (Thunnus thynnus) collected from Japanese coastal waters in order to elucidate accumulation profiles and to evaluate the suitability of this species as a biomonitor for pollution in the open sea ecosystem. Concentrations of PCBs, DDTs and CHLs in bluefin tuna increased significantly with body length (30–190 cm). HCHs and HCB residues were comparable among all the sampling regions, and the levels of these chemicals did not show correlation with body length. These results suggest significance of dietary uptake of PCBs, DDTs and CHLs compared to the intake via the gill. On the other hand, equilibrium partitioning with ambient water is a major determinant of the levels of HCHs and HCB in tuna. Body-length normalized values (BLNV) of PCBs, DDTs and CHLs concentrations in bluefin tuna were calculated using the linear regression equation obtained from the plot of concentrations and body length. BLNV of these chemicals on a lipid wt basis, which was adjusted for 100 cm body length, were indicative of the present state water pollution by PCBs, DDTs and CHLs. These results suggest that bluefin tuna is a suitable bioindicator for monitoring OCs contamination in the open sea ecosystem. 相似文献
110.
Toyoda Takahiro Fujii Yosuke Kuragano Tsurane Kosugi Naohiro Sasano Daisuke Kamachi Masafumi Ishikawa Yoichi Masuda Shuhei Sato Kanako Awaji Toshiyuki Hernandez Fabrice Ferry Nicolas Guinehut Stéphanie Martin Matthew Andrew Peterson K. Good Simon A. Valdivieso Maria Haines Keith Storto Andrea Masina Simona Köhl Armin Yin Yonghong Shi Li Alves Oscar Smith Gregory Chang You-Soon Vernieres Guillaume Wang Xiaochun Forget Gael Heimbach Patrick Wang Ou Fukumori Ichiro Lee Tong Zuo Hao Balmaseda Magdalena 《Climate Dynamics》2017,49(3):891-907
Climate Dynamics - The interannual-decadal variability of the wintertime mixed layer depths (MLDs) over the North Pacific is investigated from an empirical orthogonal function (EOF) analysis of an... 相似文献