全文获取类型
收费全文 | 177篇 |
免费 | 4篇 |
国内免费 | 6篇 |
专业分类
测绘学 | 4篇 |
大气科学 | 7篇 |
地球物理 | 26篇 |
地质学 | 115篇 |
海洋学 | 10篇 |
天文学 | 7篇 |
综合类 | 6篇 |
自然地理 | 12篇 |
出版年
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 4篇 |
2019年 | 8篇 |
2018年 | 13篇 |
2017年 | 11篇 |
2016年 | 12篇 |
2015年 | 8篇 |
2014年 | 15篇 |
2013年 | 16篇 |
2012年 | 10篇 |
2011年 | 11篇 |
2010年 | 10篇 |
2009年 | 7篇 |
2008年 | 7篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 7篇 |
2002年 | 1篇 |
2001年 | 3篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有187条查询结果,搜索用时 15 毫秒
101.
102.
Abdulkader M. Abed Saja Abu Taha Tasneem H. Hiasat Abdalla Abu Hamad 《Arabian Journal of Geosciences》2016,9(11):587
A calcrete horizon, 3–10 m thick, is found exposed in northern Jordan in three localities, Rumman, Marsa’, and Wasfi At Tal forest (WTF). It is situated at the base of the dominantly limestone, Late Cenomanian Hummar Formation, separating it from the underlying marly Fuheis Formation. The calcrete horizon exhibits all the diagnostic features characteristic of calcrete, such as diagenetic pisoids; a mottled or clotted texture; circumgranular cracks around grains in a nodular texture; pendant or microstalactitic cement; meniscus cement; plant roots or rhizogenic structures, both longitudinal and transverse; exfoliation on boulder and cobbles; alagally laminated hard pans; and abundant dissolution of cracks and vugs. Consequently, it represents a subaerial erosional unconformity and type 1 sequence boundary (SB) that was not previously noticed. The Hummar Formation is considered as a third-order sequence with the SB at the base of the calcrete horizon, while the calcrete horizon itself forms the lowstand system tracts (LST). The transgressive systems tracts (TST) involve the lower two third of the Hummar Formation ending with peloidal grainstone representing the maximum flooding surface (MFSs). The rest of the formation is the falling highstand systems tracts (HST). The next SB is not seen due to a thick soil-covered gap. The calcrete horizon formed due to the formation of a paleohigh, in the study area, associated with the compression produced by the initial subduction of the Afro-Arabian Plate under the Eurasian Plate during the Late Cenomanian, slightly earlier than the previously known Turonian subduction and compression. 相似文献
103.
104.
Thomas Stegmaier Werner Wunderlich Tom Hager Abu Bakr Siddique J. Sarsour Heinrich Planck 《洁净——土壤、空气、水》2008,36(3):279-286
Chitosan, a natural polymer, was investigated as a possible sizing agent in fabric production by appropriate modification in the textile industry. Based on recipe developments at a laboratory‐scale, the ecological and economical potential of mainly cotton yarns were demonstrated and developed. Subsequent tests within the scope of industrial production confirmed the findings of the basic developments. As an interesting alternative to the conventional sizing process involving the removal of the size after weaving, the use of appropriate processing technologies makes it possible to apply chitosan in the form of a sizing agent resistant to wash‐out processes. Therefore, the wash‐out process and the combined wastewater loading can be avoided and the properties of chitosan can be used beneficially in the later applications of the fabric. The traditional method of sizing and weaving developments as well as the analyses of material recycling showed the possibilities of using closed circuits in textile production involving sizing agent and water. It is possible that a chitosan‐specific enzyme suitable for production conditions, which facilitates the wash‐out process in combination with the biodegradation of the wastewater in a sewage plant, could be developed. 相似文献
105.
Natural Resources Research - The ~?115,000 km2 Volta Basin of Ghana is one of the most studied geological terrains. However, unlike the Birimian and Tarkwaian which have been... 相似文献
106.
南海中尺度涡温盐结构的季节特征及形成机制 总被引:2,自引:0,他引:2
本文利用最新的涡旋数据集和ARMOR3D数据,研究了南海中尺度涡温盐结构的季节特征及形成机制。合成分析的结果表明,在冬季,涡旋引起温度异常的水平分布在50米以浅表现为类似偶极型分布,而在50m以深则趋向于中心对称分布;在夏季,温度异常的水平分布均表现为中心对称的特征。涡旋引起盐度异常的水平分布也具有类似的季节特征,但是偶极型中的不对称性相对较弱。在垂向上,涡旋所致的温度异常表现为单层结构,而盐度异常则为三层结构。进一步的分析表明,涡旋所致温盐异常的垂向分布特征与背景温盐的垂向分层有关;而在50m以浅,温盐异常的水平分布的不对称特征主要由背景温盐场的水平平流所致。 相似文献
107.
Salam Roquia Ghose Bonosri Shill Badhon Kumar Islam Md. Aminul Islam Abu Reza Md. Towfiqul Sattar Md. Abdus Alam G. M. Monirul Ahmed Bayes 《Natural Hazards》2021,108(3):2589-2589
Natural Hazards - A correction to this paper has been published: https://doi.org/10.1007/s11069-021-04825-3 相似文献
108.
Al-Najjar Tariq Wahsha Mohammad Al-Khushman Mwaffaq Khalaf Maroof Hardage Kyle Hayek Wissam Khadra Khalid Abu Paytan Adina 《Ocean Science Journal》2021,56(4):364-377
Ocean Science Journal - To assess the utility of the seagrass (Halophila stipulacea) for biomonitoring of metal pollution, seagrass samples were collected from four sites along the Jordanian coast... 相似文献
109.
Modified DRASTIC assessment for intrinsic vulnerability mapping of karst aquifers: a case study 总被引:4,自引:1,他引:3
Groundwater in karstic aquifers can be dangerously sensitive to contamination. In this paper, DRASTIC assessment was modified
and applied, for the first time, to address the intrinsic vulnerability for karst aquifers. The theoretical weights of two
of DRASTIC’s parameters (aquifer media and hydraulic conductivity) were modified through sensitivity analysis. Two tests of
sensitivity analyses were carried out: the map removal and the single parameter sensitivity analyses. The modified assessment
was applied for the karst aquifers underlying Ramallah District (Palestine) as a case study. The aquifer vulnerability map
indicated that the case study area is under low, moderate and high vulnerability of groundwater to contamination. The vulnerability
index can assist in the implementation of groundwater management strategies to prevent degradation of groundwater quality.
The modified DRASTIC assessment has proven to be effective because it is relatively straightforward, use data that are commonly
available or estimated and produces an end product that is easily interpreted. 相似文献
110.
Omar Alkouri Husaini Omar Mohammed Abu Shariah Ahmad Rodzi Shattri Mansor Zainuddin Md. Yusof 《Journal of the Geological Society of India》2012,79(5):515-524
Limestone bedrock topography has complex phenomena and highly relief subsurface topography due to the presence of karstic
features. Geotechnical and environmental problems arise whenever foundations are established on the surface of the limestone
bedrock or within the overburden soils. Geographical information system (GIS) and remote sensing are emerging as powerful
techniques widely applicable in natural resources management to detect land use changes and devise strategies based on these
changes. The study focuses on using aerial photography for the detection of changes and effects of mining on geomorphology,
especially the use of sequential images that allows to detect changes taken place from time to time, by using. Volumetric
Surface Movement Spatiotemporal Data Model (VSMSDM) application has been employed to create karst terrain surface movements
and visualized 3D information in the Virtual Geographical Information Systems (VGIS). VSMSDM application was implemented by
developing prototype of visualization system using with integrated time in the TIN structure. The data have been collected
from aerial photography in 1981 and 2004, and the results displayed that the proposed data model is able to view the changing
in karst topography to detect significant landscapes and landforms changes. 相似文献