全文获取类型
收费全文 | 87篇 |
免费 | 9篇 |
国内免费 | 1篇 |
专业分类
测绘学 | 2篇 |
大气科学 | 8篇 |
地球物理 | 38篇 |
地质学 | 24篇 |
海洋学 | 16篇 |
天文学 | 8篇 |
综合类 | 1篇 |
出版年
2022年 | 1篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 6篇 |
2012年 | 5篇 |
2011年 | 7篇 |
2010年 | 5篇 |
2009年 | 7篇 |
2008年 | 3篇 |
2007年 | 8篇 |
2006年 | 6篇 |
2005年 | 1篇 |
2004年 | 6篇 |
2003年 | 9篇 |
2001年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
排序方式: 共有97条查询结果,搜索用时 0 毫秒
31.
32.
Gladys V. Melián Inés Galindo Nemesio M. Pérez Pedro A. Hernández Mario Fernández Carlos Ramírez Raúl Mora Guillermo E. Alvarado 《Pure and Applied Geophysics》2007,164(12):2465-2487
We report the results of four soil H2 surveys carried out in 2000–2003 at Poás volcano, Costa Rica, to investigate the soil H2 distribution and evaluate the diffuse H2 emission as a potential surveillance tool for Poás volcano. Soil gas H2 contents showed a wide range of concentration from 0.2 to 7,059 ppmV during the four surveys. Maps of soil gas H2 based on Sequential Gaussian Simulation showed low H2 concentration values in the soil atmosphere (<0.7 ppmV) for most of the study area, whereas high soil gas H2 values were observed inside the active crater of Poás. A significant increase in soil gas H2 concentration was observed inside the active crater during 2001 and 2002 with respect to year 2000, followed by a decrease
in 2003. The observed spatial and temporal variations of soil H2 concentration have been well correlated with seismicity, microgravimetry and fumarolic chemistry changes which occurred during
this study. These observations evidence changes in the shallow magmatic-hydrothermal system of Poás, and it might be related
to a potential magmatic intrusion during the period 1998–2004. Therefore, monitoring diffuse H2 emission of Poás has become an important geochemical tool for the monitoring of its volcanic activity. 相似文献
33.
34.
Jin?Hee?Wi Chang-Keun?Kang In?Tae?Lee Hyeon?Gyeong?JeongEmail author 《Ocean Science Journal》2018,53(4):641-653
An undescribed species of Tanaidacea was collected from Yokji Harbor in the southern coast of Korea. Hexapleomera yokjidona n. sp. can be distinguished from other species of the genus by the distinguishing features of a uropod with five articles, a pleopod basal article lacking inner seta, a mandible setal row with two setae, maxilliped coxa with two proximal setae, pereonites 1–3 together longer than wide, and pereopods 2–3 propodus with three ventral setae. To prove that H. yokjidona is a new species, detailed morphological characteristics of both genders are described and a comprehensive comparison among the species of the genus is tabulated. Additionally, diagnostic characteristics previously used to identify the species of Hexapleomera are reassessed and upgraded. 相似文献
35.
The impact of the risk environment and energy prices to the budget of Korean households 总被引:2,自引:2,他引:0
Hyungho Youn Byung In Lim Eui Young Lee YongRok Choi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(3):323-330
Energy is closely related to environmental risk. A rising fuel price in the 1970s had hurt consumers and caused disturbance
to the natural environment. Households could not afford high imported energy prices and thus resorted to fuel wood. Land competed
for fuel wood and agricultural crops, and thus high fuel prices strained the environment with respect to the use of land.
If human health and safe housing were included in environmental risk, a high energy price would induce broader environmental
risk. Households with limited income would not be able to use expensive fossil energy to warm their houses and would depend
on only electric mats or blankets to keep warm. Such insufficient warming methods would not only threaten their health but
would also worsen the condition of their houses. The abrupt increase in energy prices in 2007 and 2008 had significantly impacted
environmental risk. It forced low income households to spend more on energy, leaving less for other expenditure segments,
but had left high income households generally intact. This contrasting effect between different income groups had increased
the sustainability of the energy risks at the high prices. This study shows how risks associated with the household economy
have increased in response to the recent dramatic increases in energy prices. We develop a method for assessing risk by using
the variance of ratios of energy expenditure to current income. We then examine how differently the economic change has increased
risk across expenditure segments. We find energy expenditure as the biggest contributor to the risk. In addition, we illustrate
how energy expenditure has changed the risk profile for each income group, with the first group (i.e., the lowest income group)
experiencing the greatest increase. This group hurts the most during days of high energy prices. 相似文献
36.
Changhwan Oh Julien Legrand Kyungsik Kim Marc Philippe In SungPaik 《Journal of Asian Earth Sciences》2011,40(3):710-721
Mesozoic fossil floras are distributed over eastern Asia (China, Mongolia, Siberia, Korea and Japan) according to a regular latitudinal pattern. Two floras are usually distinguished, a northern type and a southern type, the distribution of which oscillated during the Mesozoic. In Japan, this regular pattern is disrupted by a sharp inflexion of the boundary between the two floras. Two competing hypotheses have been proposed to explain this disruption. One hypothesis advocates later tectonic motion clouding the original pattern, while the other hypothesis proposes that a warm oceanic current allowed the southern flora to grow much further north in coastal areas. We used fossil wood, a biotic component that has not previously been used, for a palaeobiogeographical study of the region. The observed fossil wood diversity at the generic level does not fit with the hypothesis of a warm oceanic current, unless this hypothesis is modified to include alternating warm northbound and cold southbound oceanic currents. Our results provide new evidence for the palaeoecology of the Mesozoic continental biota in Far-East Asia. 相似文献
37.
Carles Soriano Daniele Giordano Inés Galindo Marcel Hürlimann Paola Ardia 《Bulletin of Volcanology》2009,71(8):919-932
During rheomorphism subsequent to fallout deposition, a portion of the densely welded fallout of the La Grieta Member flowed back into the vent from where it was erupted, while the rest of it flowed down the outer slopes of the Las Cañadas caldera in Tenerife. The welded fallout and conduit-vent structure are physically connected and constitute a rare example of this type of deposits rooted to its feeder conduit and exposed in the caldera wall. The lower part of the vent-filling rheomorphic rocks shows gas bubbles and cavities that increase in size (up to 4 m) down vent. Bubbles are deformed against other bubbles, against the steep vent walls, flattened parallel to the flow foliation planes, and elongated parallel to the flow lineation and flow fold axes. The preservation of such giant bubbles, rather than their formation, seems to be a pretty unique feature of the phonolitic products investigated here and it is likely the result of the combination of factors that acted to preserve, in the surrounding of the glass transition interval, the sealing and the late stage cooling of a pressurized system. In addition, strain drop at the base of the vent-filling rheomorphic flow caused by flow stopping against vertical vent walls may have promoted rapid gas exsolution and the formation of large bubbles. 相似文献
38.
Potential increase of flood hazards in Korea due to global warming from a high-resolution regional climate simulation 总被引:1,自引:0,他引:1
Eun-Soon Im Byong-Ju Lee Ji-Hye Kwon So-Ra In Sang-Ok Han 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(1):107-113
Because of the importance of the changes in the hydrologic cycle, accurate assessment of precipitation characteristics is essential to understand the impact of climate change due to global warming. This study investigates the changes in extreme precipitation with sub-daily and daily temporal scales. For a fine-scale climate change projection focusing on the Korean peninsula (20 km), we performed the dynamical downscaling of the global climate scenario covering the period 1971?C2100 (130-year) simulated by the Max-Planck-Institute global climate model, ECHAM5, using the latest version of the International Centre for Theoretical Physics (ICTP) regional climate model, RegCM3. While annual mean precipitation exhibits a pronounced interannual and interdecadal variability, with the increasing or decreasing trend repeated during a certain period, extreme precipitation with sub-daily and daily temporal scales estimated from the generalized extreme value distribution shows consistently increasing pattern. The return period of extreme precipitation is significantly reduced despite the decreased annual mean precipitation at the end of 21st century. The decreased relatively weak precipitation is responsible for the decreased total precipitation, so that the decreased total precipitation does not necessarily mean less heavy precipitation. Climate change projection based on the ECHAM5-RegCM3 model chain clearly shows the effect of global warming in increasing the intensity and frequency of extreme precipitation, even without significantly increased total precipitation, which implies an increased risk for flood hazards. 相似文献
39.
40.
In order to deconvolve the ghost response from marine seismic data, an estimate of the ghost operator is required. Typically, this estimate is made using a model of in‐plane propagation, i.e., the ray path at the receiver falls in the vertical plane defined by the source and receiver locations. Unfortunately, this model breaks down when the source is in a crossline position relative to the receiver spread. In this situation, in‐plane signals can only exist in a small region of the signal cone. In this paper, we use Bayes' theory to model the posterior probability distribution functions for the vertical component of the ray vector given the known source–receiver azimuth and the measured inline component of the ray vector. This provides a model for the ghost delay time based on the acquisition geometry and the dip of the wave in the plane of the streamer. The model is fairly robust with regard to the prior assumptions and controlled by a single parameter that is related to the likelihood of in‐plane propagation. The expected values of the resulting distributions are consistent with the deterministic in‐plane model when in‐plane likelihood is high but valid everywhere in the signal cone. Relaxing the in‐plane likelihood to a reasonable degree radically simplifies the shape of the expected‐value surface, lending itself for use in deghosting algorithms. The model can also be extended to other plane‐wave processing problems such as interpolation. 相似文献