首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   28篇
  免费   4篇
测绘学   1篇
大气科学   1篇
地球物理   19篇
地质学   3篇
海洋学   2篇
自然地理   6篇
  2019年   3篇
  2018年   2篇
  2017年   2篇
  2016年   2篇
  2015年   7篇
  2014年   1篇
  2012年   1篇
  2011年   3篇
  2010年   2篇
  2008年   1篇
  2005年   1篇
  2004年   1篇
  2001年   2篇
  1998年   2篇
  1996年   1篇
  1984年   1篇
排序方式: 共有32条查询结果,搜索用时 15 毫秒
11.
The Zafra de Záncara anticline (also known as the El Hito anticline), located in the Loranca Cenozoic Basin (part of the Tagus Basin, Central Spain), had been studied by several oil companies during the late 1960s and early 1970s. In 2009, within the ‘Plan for selection and characterization of suitable structures of CO2 geological storage’, this anticline was selected as a potential CO2 storage site. A preliminary three-dimensional geological model, based on five geological cross sections that were constrained with the interpretation of the available seismic profiles (that are rather old and do not have very good quality), was created. With the aim of improving the geological knowledge of the Zafra de Záncara anticline and helping to investigate the suitability of a nearby anticline, namely La Rambla, as another structural closure that might make it a possible CO2 storage site, a local gravity survey (1 station every km2) was carried out in the area, seven new geological cross sections, based on these existing seismic profiles and field geology, were build, and a new three-dimensional geological model that included both anticlines, improved through three-dimensional stochastic gravity inversion, was constructed. The densities needed for the geological formations of the model come from the analysis of rock samples, logging data from El Hito-1 drillhole and petrophysical information from Instituto Geológico y Minero de España database. The inversion has improved the knowledge about the geometry of the anticlines’ traps and seals as well as the geometry of the basement relief and the structural relationship between basement and cover.  相似文献   
12.
An accurate and practical testing technique to study seismic performance of multi-storey infilled frames is formulated. This technique is based on the pseudo-dynamic method which can provide an acceptable approximation of the dynamic performance of structures under the influence of earthquake excitation. The pseudo-dynamic experimental technique is outlined and applied for testing a two-bay, two-storey gravity load designed steel frame infilled with unreinforced concrete block masonry walls. From the discussion of the results, the dynamic performance of the tested structure is assessed. © 1998 John Wiley & Sons, Ltd.  相似文献   
13.
14.
The objectives of the Istanbul Seismic Risk Mitigation and Emergency Preparedness Project are to improve Istanbul’s preparedness for a potential earthquake. Within this framework “Risk Assessment of Cultural Heritage Buildings” was designed to address the vulnerability of cultural assets, specifically buildings with global cultural heritage value. One of the components of the project was the vulnerability and risk assessment of 170 historical buildings. After a discussion of the choice of the most appropriate earthquake scenario, the methodology used for assessing the effects of local site conditions on the seismic performance of selected cultural heritage buildings is presented. The purpose is to estimate the earthquake characteristics on the ground surface based on the earthquake characteristics on the engineering bedrock outcrop obtained from the probabilistic and deterministic hazard studies. The site specific elastic design spectra for each site are then further manipulated to obtain site specific non linear displacement spectra, so that these can be directly compared with capacity curves for the buildings obtained by using plasticity based limit state analysis. The procedure for obtaining the capacity curves is described and the choice of the most appropriate level of ductility and the equivalent reduction coefficient are discussed. A procedure to evaluate performance points and to define safety factors based on lateral acceleration, drift or expected damage level, is presented. The process of arriving at a risk evaluation and hence recommendation for strengthening or otherwise, is finally highlighted with respect to two comparable case studies.  相似文献   
15.
16.
17.
18.
Experimental studies on the retention of metals (Cu, Co, Ni, and Zn) in bentonite samples from the Grau Region (Northern Peru) have been accomplished using monometallic, bimetallic, trimetallic, and tetrametallic solutions. Parameters such as pH and concentration of dissolved metals and organic compounds have been evaluated by means of batch adsorption experiments. Adsorption rates indicate the suitability of these bentonites in the environmental industry for heavy metals retention purposes. In addition to its quality as physical barrier to avoid the dispersion through the environment of polluted leachates, bentonite, due to its high cation exchange capacity, can act also as a chemical barrier, protecting the quality of surface and groundwater systems, while limiting the migration of heavy metals in solid residues or sludge stocked in security landfills. Adsorption rates of tested bentonites were proved to decrease when concentrations of both metal and organic compounds, as well as the number of ionic species, increase in solution; additionally, lower metal removal rates from solution were obtained when extremely acidic conditions were achieved.  相似文献   
19.
Roads, particularly since the advent of motorized traffic, have hugely impacted contemporary landscapes. Although their significance was noted in the 1980s, specific roadway‐heritage studies are scarce. Research in different disciplines has identified certain features of roads, but an integrated approach to roadway heritage or a consensus on what this constitutes are lacking. This article proposes an interdisciplinary methodology to assess roadway heritage. Roadways are interpreted within the framework of semantic openness that currently characterizes heritage studies, territory being the basic element of interpretation. Rather than a fragmented approach to conservation, the research defines integrated heritage configurations where natural, cultural, and historical features combine to produce a cohesive form of heritage. GIS (Geographical information systems) technology is used with an online database to assess the complexity of roadway heritage. ICT (Information and communications technology) strategies to raise public awareness are outlined. The methodology is applied to assess the historical N‐340 Mediterranean roadway corridor in Spain.  相似文献   
20.
We apply the process‐based, distributed TOPKAPI‐ETH glacio‐hydrological model to a glacierized catchment (19% glacierized) in the semiarid Andes of central Chile. The semiarid Andes provides vital freshwater resources to valleys in Chile and Argentina, but only few glacio‐hydrological modelling studies have been conducted, and its dominant hydrological processes remain poorly understood. The catchment contains two debris‐free glaciers reaching down to 3900 m asl (Bello and Yeso glaciers) and one debris‐covered avalanche‐fed glacier reaching to 3200 m asl (Piramide Glacier). Our main objective is to compare the mass balance and runoff contributions of both glacier types under current climatic conditions. We use a unique dataset of field measurements collected over two ablation seasons combined with the distributed TOPKAPI‐ETH model that includes physically oriented parameterizations of snow and ice ablation, gravitational distribution of snow, snow albedo evolution and the ablation of debris‐covered ice. Model outputs indicate that while the mass balance of Bello and Yeso glaciers is mostly explained by temperature gradients, the Piramide Glacier mass balance is governed by debris thickness and avalanches and has a clear non‐linear profile with elevation as a result. Despite the thermal insulation effect of the debris cover, the mass balance and contribution to runoff from debris‐free and debris‐covered glaciers are similar in magnitude, mainly because of elevation differences. However, runoff contributions are distinct in time and seasonality with ice melt starting approximately four weeks earlier from the debris‐covered glacier, what is of relevance for water resources management. At the catchment scale, snowmelt is the dominant contributor to runoff during both years. However, during the driest year of our simulations, ice melt contributes 42 ± 8% and 67 ± 6% of the annual and summer runoff, respectively. Sensitivity analyses show that runoff is most sensitive to temperature and precipitation gradients, melt factors and debris cover thickness. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号