全文获取类型
收费全文 | 1395篇 |
免费 | 97篇 |
国内免费 | 13篇 |
专业分类
测绘学 | 38篇 |
大气科学 | 137篇 |
地球物理 | 413篇 |
地质学 | 513篇 |
海洋学 | 144篇 |
天文学 | 151篇 |
综合类 | 3篇 |
自然地理 | 106篇 |
出版年
2023年 | 7篇 |
2022年 | 10篇 |
2021年 | 33篇 |
2020年 | 26篇 |
2019年 | 28篇 |
2018年 | 72篇 |
2017年 | 81篇 |
2016年 | 88篇 |
2015年 | 58篇 |
2014年 | 69篇 |
2013年 | 98篇 |
2012年 | 92篇 |
2011年 | 72篇 |
2010年 | 80篇 |
2009年 | 78篇 |
2008年 | 74篇 |
2007年 | 51篇 |
2006年 | 39篇 |
2005年 | 31篇 |
2004年 | 37篇 |
2003年 | 31篇 |
2002年 | 38篇 |
2001年 | 18篇 |
2000年 | 15篇 |
1999年 | 12篇 |
1998年 | 11篇 |
1997年 | 13篇 |
1996年 | 14篇 |
1995年 | 17篇 |
1994年 | 14篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 11篇 |
1988年 | 7篇 |
1987年 | 10篇 |
1985年 | 11篇 |
1984年 | 11篇 |
1982年 | 10篇 |
1981年 | 12篇 |
1980年 | 8篇 |
1979年 | 5篇 |
1977年 | 11篇 |
1975年 | 8篇 |
1974年 | 5篇 |
1957年 | 4篇 |
1955年 | 4篇 |
1953年 | 6篇 |
1951年 | 4篇 |
1948年 | 4篇 |
排序方式: 共有1505条查询结果,搜索用时 165 毫秒
51.
52.
Joong-Bae Ahn Sera Jo Myoung-Seok Suh Dong-Hyun Cha Dong-Kyou Lee Song-You Hong Seung-Ki Min Seong-Chan Park Hyun-Suk Kang Kyo-Moon Shim 《Asia-Pacific Journal of Atmospheric Sciences》2016,52(2):223-236
The change of extreme precipitation is assessed with the HadGEM2-AO - 5 Regional Climate Models (RCMs) chain, which is a national downscaling project undertaken cooperatively by several South Korean institutes aimed at producing regional climate change projection with fine resolution (12.5 km) around the Korean Peninsula. The downscaling domain, resolution and lateral boundary conditions are held the same among the 5 RCMs to minimize the uncertainties from model configuration. Climatological changes reveal a statistically significant increase in the mid-21st century (2046- 2070; Fut1) and the late-21st century (2076-2100; Fut2) precipitation properties related to extreme precipitation, such as precipitation intensity and average of upper 5 percentile daily precipitation, with respect to the reference period (1981-2005). Changes depending on the intensity categories also present a clear trend of decreasing light rain and increasing heavy rain. In accordance with these results, the change of 1-in-50 year maximum precipitation intensity over South Korea is estimated by the GEV method. The result suggests that the 50-year return value (RV50) will change from -32.69% to 72.7% and from -31.6% to 96.32% in Fut1 and from -31.97% to 86.25% and from -19.45% to 134.88% in Fut2 under representative concentration pathway (RCP) 4.5 and 8.5 scenarios, respectively, at the 90% confidence level. This study suggests that multi-RCMs can be used to reduce uncertainties and assess the future change of extreme precipitation more reliably. Moreover, future projection of the regional climate change contains uncertainties evoked from not only driving GCM but also RCM. Therefore, multi-GCM and multi-RCM studies are expected to provide more robust projection. 相似文献
53.
54.
An Alternative Protocol for Single Zircon Dissolution with Application to (U‐Th‐Sm)/He Thermochronometry 下载免费PDF全文
Bouchaïb Tibari Arnaud Vacherat Martin Stab Raphaël Pik Delphine Yeghicheyan Pascal Hild 《Geostandards and Geoanalytical Research》2016,40(3):365-375
Zircon (U‐Th‐Sm)/He (ZHe) thermochronometry is a powerful tool that has been widely used in geology to constrain the exhumation histories of orogens. In this study, we present an alternative protocol for dissolving zircon grains for determination of parent nuclides. This new alkali fusion procedure developed at the SARM (Service d'Analyse des Roches et des Minéraux) in Nancy, France, is fast (requiring only 2 d, including cleaning steps) and offers several advantages over conventional methods by avoiding: (i) use of HF pressure dissolution and (ii) complete removing of grains from the metal microvials. After dissolution, U, Th and Sm were measured using an ICP‐MS. We tested the new procedure on two different ZHe reference materials, the Fish Canyon Tuff and Buluk Tuff; these provided precision values for ZHe‐age estimations of 9 and 6% (1s), respectively. In addition, using this method, zircons from the Buluk Tuff are shown to be chemically more homogenous and more suitable for assessing the uncertainty of the entire integrated procedure. 相似文献
55.
Jo Beth Mullens 《The Journal of geography》2016,115(6):244-255
Charging undergraduate geography students with the task of designing a recreational trail in their local community offers an engaging experiential opportunity with potential to advance geographic learning in a real-world setting. This article presents an assignment in which students were asked to develop a recreational trail proposal for an undeveloped local conservation area and the results of a survey that asked the students to reflect and report upon the educational value of this experience one year later. Results of the survey validated the assignment's lasting value to the students across the cognitive, psychomotor, and affective learning domains. 相似文献
56.
57.
58.
59.
A single specimen of the pelagic shrimps, Pasiphaea japonica Omori, 1976 (Pasiphaeidae) collected in the southeastern waters of Korea is described and illustrated. Although this species occurs widely in the Indo-West Pacific including the Japanese coast of the East/Japan Sea and the middle and southern parts of the East China Sea, this is the first record of the species and the genus in Korean waters. The species is distinguished from other congeners by the following combination of characteristics: non-carinate dorsal sixth abdominal somite with a terminal tooth, rudimentary pleurobranch on the eighth thoracic somite, merus of the first pereopod with more than eight spines, and almost entirely transparent white color. 相似文献
60.
Hydrocarbon reservoir modelling and characterisation is a challenging subject within the oil and gas industry due to the lack of well data and the natural heterogeneities of the Earth’s subsurface. Integrating historical production data into the geo-modelling workflow, commonly designated by history matching, allows better reservoir characterisation and the possibility of predicting the reservoir behaviour. We present herein a geostatistical-based multi-objective history matching methodology. It starts with the generation of an initial ensemble of the subsurface petrophysical property of interest through stochastic sequential simulation. Each model is then ranked according the match between its dynamic response, after fluid flow simulation, and the observed available historical production data. This enables building regionalised Pareto fronts and the definition of a large ensemble of optimal subsurface Earth models that fit all the observed production data without compromising the exploration of the uncertainty space. The proposed geostatistical multi-objective history matching technique is successfully implemented in a benchmark synthetic reservoir dataset, the PUNQ-S3, where 12 objectives are targeted. 相似文献